i've drafted in a 10-team and an 8-team league where we start 2 QBs.
In the 10-team league, Brady went first round, Manning, Romo, Brees, Ben in the 2nd, DA and Palmer the 3rd, McNabb and Hasselbeck the 4th. The only guys to really "hold off" on drafting a QB drafted their 1st QB in the 5th, and then their 2nd in the 6th.
In the 8-team league, it was similar, except I picked Brady and Brees in the 1st and 2nd round. I turned around and traded Brady + Calvin Johnson + Michael Turner and got Cutler, Steven Jackson and Terrell Owens in return. I'm pretty confident I won out on that deal as QBs only get 4 points / TD in that league. It's a risk drafting 2 QBs early as it pushes some pretty solid names down the list at other positions (you won't see TO going 3rd round in too many PPR leagues otherwise)