I have a friend at work that bought a Walmart bike 2 years ago for about 100 bucks and rides it as a commuter bike about 1 mile to work each day and on the weekend in the summer might do up to a 10 mile ride on trails a dozen time. It is a Mountain like bike triple chain ring suspension bike. The rest of the time it sits indoors at work and in his house. He brought it home and spent a few hours going over it and greased it and oiled it typical stuff they didn’t do well at assembly and he retightened everything. He added another 50 dollars’ worth of add on stuff from Walmart a rack, lights and some bags on the back for his stuff. I can see that bike lasting him till he retires in 20 years no problem the way he uses it and the way he maintains it.
I voted no in your poll because I have bought at least a dozen used bikes off CL for half the amount he paid that I would never trade for his Walmart bike brand new. So in my case I wouldn’t want one. But then again you have to know what you are looking for in a used bike of quality and know if it is wore out or lightly used, and in both cases the bike needs to be gone over before I would ride it. The trouble people have with buying a Walmart bike and then taking it to a bike shop and asking them if they could go over the bike and give it a good tune up is they will likely charge you about half the price of the bike to do that.
if my friend was advising you I know he would say go for it. It is really amazing they can build anything of any quality for that price. I know firsthand from seeing hundreds of cheap bikes at garage sales and around if you give one to a kid and they get used as most kids use a bike with leaving them out in the rain and all around beating on them they last about one summer.
You didn’t mention the fit and your size and weight. I wouldn’t recommend one at all to someone pretty heavy. Wheels and spokes really come into the discussion then and once the wheels start going the bike is done.
Hope this helps.