People have a tendancy to learn things the hard way. It seems to be in the nature of people to believe that what happens to one person will not likely happen to them. I like to try to learn from someone else's mistakes, if possible. In a case like this, you are not likely to save a whole lot of money, assuming that's your motivation, and stand quite likely to have problems. I have talked, in person, to probably 5 different people who have had actual experiences with Bob, and they all say the same thing. That does not even begin to include the list of folks here on this board who have also had bad experiences with him. IMHO, if you decide to buy from a person who has an established reputation as a complete asshole who sells shotty merchandise, you are asking for trouble. But alas, the decision is yours to make.
What about RRA? Good prices, and they seem to be held in very high regard.