Burnett is a lot more stable than Sheets.
Sheets starts over the last 4 yrs
22, 17, 24, 31- 23.5 starts per season
Burnett over the last 4 yrs
32, 21, 25, 35- 28.3 starts per season
3 of the top 4 start totals are Burnett's above. AND Sheets is currently injured, while Burnett was not. Listen, I happen to think that Sheets will be healthy for the next few seasons, but I have nothing but my gut to back that up, and we know how reliable that has been.