memilanuk said:Heavy Palma or similar, possibly fluted if you need to shave weight. Plenty of Medium Palma contour barrels out there as well. 30" is the norm; a few people go longer in an effort to pick up some 'free' MV or maybe experiment with hitting a particular accuracy node. Longer than 30" starts getting to be more difficult (not impossible) to find a case that fits, though.
10 twist would cover pretty much any of the available options that you might want to run. 11 should work up to the 200-210s, might be iffy @ 215-230 if'n you desire to experiment in that direction.
Dave Kiff @ PTG has an F/TR reamer with a 0.168" freebore that works well for a lot of people; there is also a '2013 US FTR' reamer that Kiff makes that is basically a '95 Palma chamber (well tested and proven) with a 0.170" freebore. Probably not enough difference between the two to argue over, but figured I'd throw it out there.