Well, depends how deep your pockets are and how easily you are satisfied. Are you younger, older? I mean, if you're my age, and I'm 19, you probably don't want to be driving a 350+hp car unless you have tons of self control, because the temptation is always there. You can still get power out of a single turbo, yes. Realistically, I'll bet you could be running low 13's with a single turbo R tuned correctly, maybe even high 12's. But obviously VW's aren't all about the 1/4. The other thing is to make sure your suspension and brakes can handle the extra power. Doesn't do you any good if you can't stop well or take a corner.