my hatred for cheap walmart bikes is well documented on this forum, as well as horror stories from lots of other people with their actual experiences motorizing these things.
i've realized that it's a losing battle to keep arguing about how poorly made they are, and for the first time builder, the guy on the cheap, and the weekend cruiser, it's a good way to go. it's also a good bike to buy if you're a fad oriented type of person who just wants the latest toy, and plan on dumping it on craigslist in 6 months. or the guy hoping to make a quick buck by buying cheap and selling high.
for long term usage, reliability to and from work or school everyday, or a performance minded person, it's the worst choice possible.
i refer to them as disposable, or throw-away bikes, 'cause a lot of the weekly, summer renters at the beaches here will buy them, use them for the two weeks they're here, then abandon them or try to get 25-30 bucks for 'em on craigslist. my buddy lives on the beach in Newport, and the weekly's who just left gave him 3 almost brand new bikes, for nothing. and they ain't getting motors on them. they'll be pub cruisers at best.
i don't wanna open up the same can of worms with my post, but the title, "debunking myths..." kinda strikes a nerve. i could break down a walmart bike piece by piece and give you factual, technical, as well as anecdotal information about the "quality" of it.
but, if it works for you, who cares what other people say, right?