On Pole

Pirelli Trofeo are made to drive to and from the track. I just drove from Maryland to Savannah GA to instruct for the National Ferrari Meet for three days on them.

IRguy

Altough I do not have yet any GT3 RS experience with the BFG-R1's I used them for 2 years (along with R6's) on the M3. You have to take my opinion with a grain of salt since I am not a professional driver.
I liked the BFG-R1 a lot. They provide better grip than MPSC's but sometimes I felt thay they are not as sticky than the R6. They need a little bit mora warm up than the R6 I think. They are sensitive to temp. (R6 too) but maybe less so. They heatcycle out somewhat latter than the R6 and possibly the steering is a tad sharper. They have stiff sidewalls. R6 are lighter at the same size.
Overall they felt slightly more durable, less grippy, and min more precise on the M3 than the R6. I could not really detect any significant time difference between the R6 and BFG-R1 but maybe the R6 is a little bit faster. Again, temp is an issue. As a disclaimer, I never had both of them back to back on the car!! But they are about 4-6 sec faster on an avarge 1min 48sec lap (M3) track than the PS2-s and about 2-3 sec better than the MPSC.
I hope this helsp some!
Will tell you more when I have them on the GT3 RS.