Personally, I like the rebuy because it balanced out luck and skills. For example, your skills is 8 and your opponents are at 4. Luck might be not on your side when you go all in w/ KK and then the flop gives your opponent a straight. That's bad luck. the rebuy could help you get back in the game and eventually the probability of your skills overcomes bad luck would let you get into the bubble. Therefore, I like the rebuy and trying my best to build my BR to get to do some more rebuy torunies.