Going back to the NXR and Thor brands listed in your original post, and whether they are "seriously problematic." The answer is, it depends.
You've no doubt seen the extensive past threads here on the NXR ranges and the more recent two or three (though not so extensive) threads here on the Thor ranges. Both brands are assembled/fabricated in China by Dongguan Hyxion Works for sale to and through US based import marketing companies. Post sale support is not great. The current models are pretty much the same as the older ones except for some having features like more LED indicator lights and some models now being more "downmarket" which might be what you have been looking at. Basically, the differences between the lower priced and higher-priced versions of current model lines pretty much come down the burner size and arrangements and a few glitzy features like LED indicator lights.
I would say these are not "seriously problematic" if you are good at DIY repairs and are comfortable with scrounging generic replacement parts when needed. Have you run across the threads here where I and other NXR owners have discussed DIY fixes (See, for example, if-susan-fixed-her-nxr-oven-ignitor-u-can-2) If not, I might summarize by saying that these ranges are mostly old style designs from back when we expected to have to fiddle with and fix things much as you might do if you bought an imported knock-off of an old, manual everything Jeep. Fine if you like doing back-country rock climbs or live on a ranch where you need high-ground-clearance, need 4wd/awd, need manual-everything, and have the tools and skills to keep them running. Not so good as an urban daily driver for those who don't have both the time, skills and interest in fixing niggling things that will come up that need adjusting or replacing from time to time.
BTW, these things will need a good vent hood. Do you already have one or are you planning on installing one?
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