Let's do a little logic 101. The position of those who defend the rivals rating system (i.e., who generally believe it's better to get 4 and 5 star guys than 2 and 3 star guys) is not that all 4 and 5 star guys are going to be better players than 2 and 3 star guys. The position is rather that a greater percentage of 4 and 5 star guys become college stars than 2 and 3 star guys (and therefore, the more 4 and 5 star guys you get on your team, the more likely your team is to have a greater number of college stars). You don't refute this position by toting out a 3 star guy who made good (a la Colt McCoy) and saying "Well, how 'bout this fellow. He wasn't rated very high and he did well for himself." That's a fine argument if the position had been the former position (i.e., no 3 star guy could ever out perform a 4 or 5 star guy), but it's a non-starter against the second position (i.e., generally speaking, a greater percentage of 4 and 5 star guys pan out than 2 and 3 star guys). The way you refute the second position is showing that a greater percentage (not number) of 2 and 3 star guys become college stars than 4 and 5 star guys. I have yet to see anyone make that argument, and until they do, I'm going to believe that it's better for Tennessee to get 4 and 5 star guys than 2 and 3 star guys.
Think about it this way: Suppose you have to choose to believe one of two weather forecasts and all you know is that one forecast is correct 80% of the time, and the other forecast is correct 40% of the time. Wouldn't you opt for the 80% forecast? That doesn't mean that there aren't going to be times when the 40% forecast is correct and the 80% forecast incorrect. But it doesn't follow from that that you should start going with the 40% forecast instead of the 80% forecast.