I like re-buy mtts.
I always late register at the last minute, take the re-buy, then take the add-on.
depending on structure, I can easily be sitting on 35+ bbs in the late stages of an mtt with 60-75% of the field gone, playing for a bloated prize pool thanks to all the re-buys. I basically let people do all the dirty work, then give myself a huge chance to win it because I have to get through fewer players.
another good thing about re-buy mtts is that it's better for your overall roi because you usually only pay rake once, depending on site. compared to re-entry mtts, where you pay the rake each time you buy-in.
using my buy-in / re-buy/ add-on strategy above, I'm only paying the initial buy in rake. so, if it's a $1 + .10 buy-in, I'm paying $3 + .10 in total. if I played a re-entry mtt and re-entered 3x, I'm paying $3 + .30 in total. let's say i cash for $10 in each game. this gives me an roi of 222.5% for the re-buy and 203% for the re-entry.
at the same time, my chances of running deep are going to be in the re-buy mtt with a larger starting stack compared to the re-entry. even if I buy-in only once into the re-entry, I either have to get through more opponents or I buy late with a much smaller starting stack. so, I spend less on the buy-in, but
odds of running deep are worse.
you do need a much bigger bankroll to fund re-buy mtts and whatever your stop-loss point is.