Is it worth it to play in tournaments with re-buys, without rebuying?

[sh1fty]

I'm a micro limits player and have steered clear of anything past $4, because of the rebuys/addons. I have won a few $4, $3, $1 tourneys etc slowly building my bankroll. I would love to have a shot at some of these huge tourneys that are only $5 or like $10.

Rebuys and Addons scare me because as a micro limits player each $5 I lose is a reasonable amount of my bankroll. Does the ability to rebuy and add on your chips make players more aggressive, and do players just addon chips until they have such a huge advantage it's too hard to play with them off the bat?