when to rebuy?

[crockpot]

in either a NLHE or PLO game, say a bad hand just knocked your stack down to less than half the maximum buy-in at your table, and you're in fairly early position. you want to buy back to the maximum. do you do it now, or wait until you'll be on the button so you can have good position with the bigger stack?

i'm wondering whether the bigger stack and thus the ability to get more value from a big hand is worth sacrificing the potential to get all-in easily and thus negate an opponent's positional advantage. plus, with more chips you may be forced out of a pot by an aggressive player's positional raises when you could have gotten all-in with a shorter stack.

thoughts on this?