Eli, Peyton, Romo, Rivers, Ryan, Vick, etc.. all those guys don't go till the 7th/8th round. If you want RG3 you can wait till 11th/12th round to get him. If you're that pressed than sure, get him early but you'd be passing up on another O player to another manager in your league.
I'm hoping for big things from the kid but given the fact you can get 2 well proven QBs I'm not sure why you'd want him on your fant. team.