Well, I'm not building a robot this year, but in 2006 one FP worked okay.
http://www.youtube.com/watch?v=jggKd...fOxsD6WqKj3HO_
Looking back, our original intent was to have a second FP on the other side of the turret, so the shooter would run off 2 FP's. This would have been good as far as getting our shot rate up, but would have also meant that we would have violated the maximum ball velocity rule that was in place that year... we weren't sufficiently skilled at sensors and software at that point to have a constant-speed closed-loop feedback system on the shooter motor(s).
While the full pan/tilt turret looks really good, and we could hit from half court, and this became our #1 demo robot for years, we got whupped by teams with simpler mechanisms who could aim and shoot more balls from closer range.... and that was with a much larger target to aim at.
I don't know how much more energy the larger balls this year will require, but I suspect 2 CIMs will have more than enough energy to hit the target from wherever you choose to shoot.
Jason