Had the same problem with turbo but on lower stakes. Every time I tried to star playing turbo I got couple of bad beats and thought it is impossible to have some nice ROI on turbo games. I suppose in fact it is impossible to hold up ROI from regular games because of greater variance. My problem was with too many all ins preflop. On a higher blinds (25-50) I shoved way to often with hands like AJo to steal 2x or 3x raise from button. Even though often I was called by a weaker hand like KTs I was loosing quite a lot of games - probably even more than I should according to statistics... But this is problem with shoving preflop
Quite a high variance...