Kuroda or Sheets...
I wouldn't be dropping Carmona, he worked a lot in the offseason on all of his pitches, and I don't think that those 19 Ws 3 years ago was a fluke. Remember he has had injuries the last 2 seasons, and thus far looks to be back to 100%. In my eyes I wouldn't trust Sheets as far as I can throw him and coming in at or above 230, I can't throw him very far. Remember with Sheets even WHEN healthy he has never won more then 13 games and has only topped 11 Ws 3 times, everyone is hung up on stats from 2004 when he struck out 260+ batters, and aside from that has struck out 160+ only one other time. So taking that into consideration also taking his injuries into consideration, expecting 9-11 Ws and 160Ks is asking QUITE a bit in my opinion.
In short I would take Lilly over either Kuroda or Sheets any day of the week.