it depends on what 'bang for your buck' means in your case.
Personally I play almost only the turbos these days and had only ever played reg. speed previously... BUT I've done a ton of reading/studying on sng play and more specifically (recently) turbo play. So for myself, this is where I can run a +ROI.
For a micro buyin, if you want to play a game with really bad players... there's a sng satellite for the Midinght Madness running each day, roughly between 21:00 & 22:00 est. There you will find just about the worst play on Fulltilt. If you have patience for it, these can be very easy to cash in (but of course at the same time, you will experience more badbeats in them then most others). Pays out $11 to 1st & 2nd, $5 for 3rd. I played them last week and was in the money in 8 of 9 I played (then tried them again this week, lost the first couple and haven't played them since, lol).
I would also strongly suggest the 9plyr. sngs over the others.
Oh yah, another really bad sng (as far as worst play goes) is the $3 90-plyr.KO. I find it to be pretty bad,... some seem to like it??
If you could define what you were meaning by 'bang for your buck',.. I think I could be more specific in my answer.