Re: High Speed Rear Blowouts
The last time that I checked at the bike store, the cheapest bike was $350. This was just a basic mountain bike with front suspension, whereas Walmart bikes are $99 and for many people hold up just fine for what they do with them. For a quality bike today, you will need to spend $500+ and for many casual bikers, I don't see that happening.
I would just make sure as a rule of thumb that moving parts on any bike are in good condition.