REASONS TO BUY
Good at defrosting meat
REASONS TO AVOID
Not the most convenient to use
Heating performance could be better
Panasonic NN-SB458S Review
This product pairs average results with an average price, failing to stand out from the competition
RELATED: Best Microwaves of 2023
Our Verdict
Earning decently favorable results across the board in our best microwave testing, we wouldn't actively dissuade anyone from purchasing the Panasonic NN-SB458S. It did average or above average across our four performance metrics, and we don't think it's overly expensive in the world of kitchen appliances. This isn't our favorite microwave by any means, with multiple other products considerably outperforming it, but it gets the job done.
Editor's Note: This product review was updated on January 11, 2022 with further recommendations and comparison information.
Compare to Similar Products
 This Product
Panasonic NN-SB458S | |||||
|---|---|---|---|---|---|
| Awards | |||||
| Price | $110 List $119.95 at Amazon | $127 List | $115 List $102.99 at Amazon | $120 List $129.56 at Amazon | $90 List $87.66 at Amazon |
Overall Score  |
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| Star Rating | |||||
| Pros | Good at defrosting meat | Great popcorn, convenient one-touch buttons, quick water heating | Easy to use, relatively inexpensive, excellent with prepared frozen items | Good at reheating, does well with premade frozen foods | Did well at defrosting, fairly inexpensive |
| Cons | Not the most convenient to use, heating performance could be better | Inconsistent heating, lackluster defrosting, underwhelming | Struggled to defrost the ground turkey | Didn't defrost frozen turkey well | Struggled with some frozen foods, so-so heating results |
| Bottom Line | This product pairs average results with an average price, failing to stand out from the competition | This microwave performed average overall with a higher price tag than products performing similarly | This product had mixed results overall, failing to distinguish it all that much from other products | This larger product did decently well but we don't think it quite matches the performance of the top-tier models | This product failed to impress us too much, ranking close to the bottom of the overall |
| Rating Categories | Panasonic NN-SB458S | Farberware Classic... | Toshiba EM925A5A | Black+Decker EM031MB11 | Black+Decker EM720CB7 |
| Heating (40%) | |||||
| Frozen Foods (30%) | |||||
| Defrosting (20%) | |||||
| Ease of use (10%) | |||||
| Specs | Panasonic NN-SB458S | Farberware Classic... | Toshiba EM925A5A | Black+Decker EM031MB11 | Black+Decker EM720CB7 |
| Wattage | 900 watts | 1000 watts | 900 watts | 1000 watts | 700 watts |
| Size | 0.9 cu. ft. | 1.1 cu. ft. | 0.9 cu. ft. | 1.1 cu. ft. | 0.7 cu. ft. |
| Dimensions (WxHxD) | 19.1" x 11.5" x 14.8" | 20.2" x 12.1" x 16.5" | 19.2" x 11.5" x 15.9" | 20.2" x 12.1" x 15.6" | 17.3" x 10.3" x 13.0" |
| Turntable Diameter | 10.6" | 12.4" | 10.6" | 12.4" | 10.0" |
| Internal Dimentions (WxHxD) | 13.9" x 8.1" x 12.4" | 12.9" x 8.1" x 14" | 13.7" x 8.7" x 12.3" | 14.5" x 9.1" x 13.9" | 12.1" x 8.1" x 12.0" |
| Child lock | Yes | Yes | Yes | Yes | Yes |
| 45 Sec Heating Temp Rise | 89 F | 109 F | 89 F | 83 F | 73 F |
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Our Analysis and Test Results
Though this model delivered one of the best microwave performances of the entire test suite with the frozen burrito and had one of the better popcorn presets, we wouldn't base a purchase decision on those factors alone. However, they might be something to keep in mind if you are considering this particular model.
Performance Comparison
This product delivered on overall above-average performance.
Credit: Laura Casner
Likes
As mentioned above, the Panasonic NN-SB458S delivered its most noteworthy performances with frozen foods — both with premade frozen foods and when defrosting frozen ground turkey. This kitchen appliance exceptionally impressed us with its performance in the burrito test, with the left, right, and center zones only showing an average temperature difference of only 3°F, with the entire burrito warmed up both above the recommended temperature and warm enough to serve in the opinion of our testers.
We found that one side was just a tiny bit cooler than the rest during our Panasonic NN-SB458S heat test.
Credit: Laura Casner
It did almost as well with the Hot Pocket, with the average temperature difference only increasing to around 7°F. However, the NN-SB458S lost a few points for slightly burning one end, getting it a little crustier than we would have liked.
The Panasonic NN-SB458S continued its strong showing into the defrosting test. This microwave completely defrosted 8.75 ounces of the one-pound block, and the remaining part very easily broke apart — enough that we would have felt fine to toss everything right into the pan. It had an alert to let us know when it was time to flip the turkey a few minutes into the process, and we appreciated that it didn't cook any of the meat prematurely.
This appliance thawed just a bit more than half of the turkey.
Credit: Laura Casner
The NN-SB458S performed a bit better than average in some of our heating tests. It heated the 125 mL of water very quickly, raising its temperature to almost 90°F after 45 seconds of heating. It also did exceptionally well with our plate of leftovers using its auto-reheat function. The sausage, potatoes, and green beans weren't too far apart in temperature, and all three were warm enough to eat without additional time in the microwave, something we couldn't say about every model.
We feel that you could have served this plate immediately after the initial heating.
Credit: Laura Casner
The Panasonic NN-SB458S also did an above-average job at reheating the canned soup, getting it more than warm enough when we followed the heating instructions.
We did dock some points for these two slices coming out with some significant thermal differences.
Credit: Laura Casner
Dislikes
The Panasonic NN-SB458S delivered some relatively poor results when it came to reheating pizza. The two slices were heated very unevenly, with one slice being far from hot enough to eat and the other exhibiting significant temperature discrepancies.
The heat map right after heating.
Credit: Laura Casner
We weren't amazingly impressed with this appliance's performance in our heat map tests. Some areas were completely burnt, while others were still browning.
You can see the differences in heating clearly here.
Credit: Laura Casner
The NN-SB458S also disappointed us somewhat with its performance at heating the individual miniature lasagna. Overall, it wasn't heated quite enough, and there were substantial temperature discrepancies between the six points we measured — one as large as 52°F.
The Panasonic NN-SB458S doesn't have quite as many convenience features as some of the others.
Credit: Laura Casner
We also found this product to be a little less user-friendly compared to some of the competition. The +30 seconds button doesn't automatically start the appliance, and it lacks any one-touch features. Its internal light isn't terribly bright, and we found that the unit easily slides around when you push a button or open/close the door if it's on any sort of slick countertop.
While we didn't find this product to be the best, we still think it's a pretty good option.
Credit: Laura Casner
Should You Buy the Panasonic NN-SB458S?
The Panasonic NN-SB458S provides a decent value as a garden variety microwave offered at a reasonable price. It has a few noteworthy performances (it was stellar with leftovers, although not with leftover pizza), but overall we'd point you in the direction of one of the other better options in the group.
What Other Microwaves Should You Consider?
For a top-of-the-line product that performs well, we'd point just about anyone towards the Toshiba EM131A5C. Anyone intending on mainly cooking frozen foods in their microwave can't go wrong with the Panasonic NN-SN67KS.
—
David Wise and Austin Palmer
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