Which is better ROI, 800 chips or 1500 chips..in general

[spikeanut]

Well I'm an occasional 20/30 SNG at Stars. Online poker is really a hobby for me, for when my live games are running bad. I'm just curious as to how everyone is faring in these different chip counts? At stars, I'll normally 3-4 table, with either 2/2 or 3 20's and a single 30. So I am by no means a spectacular SNG player, but I have been pretty consistent in the last 400-500 SNGs, with a ROI of 16.7%. Now my question is, should I continue to grind it out at stars, with each SNG taking 45-60 mins. Or should I move over to party where I hear the SNGs are much faster, and are more or less a wait for a monster type game. I would have no problem playing a mechanical game at party, if it meant faster SNGs. What buy-in should I start on over there, are the players at those buy-ins fairly similar to stars? I really don't mind playing the occasional sub-par poker, if it means a lot less thinking, and a higher ROI, I'm all for that. What are your experiences between these two chip counts?