I would guess that a bike that cheap has the worst quality components. Take a look at a $150 Walmart bike and you'll get some idea of the level of quality to expect. I looked at the brakes on a BSO and they were fairly thin stamped sheet metal and looked like would flex easily. Of course these could be the last 20 bikes from four years ago that they just want to get rid of and might be comparable in quality to a $500 bike. Reviews are tricky, because you don't know much about the reviewer. I would put more faith on a review seen here on the forums by someone with more than 5 posts :-)
I've started doing weekend errands by bike because driving in the bay area has turned into mostly waiting. So much high density housing going in, and road diets and you end up with more lights and stop signs. The 8 mile bike ride from Satan Clara to Mountain View is easy enough.