For the most part, the Amazon 5-star system is pretty trustworthy, but it can be rigged. Although Amazon does a good job mitigating the possibility, sellers can find ways around to add fake positive reviews. This is not to say you shouldn't read the online reviews. You definitely should take the time to see what other people are saying before you buy, and there are a few ways to protect yourself. For starters, if there are an abnormal number of glowing reviews that don't point out any negative aspects, there could be some manipulation. Also look for a flag next to the reviewer that indicates they're a "verified buyer."