As I've said like 8800x now, I have the 8800 and love it. But I'm curious where you'd mount a 2900 in the 100- the remote face seems to be the default for the 100 series setups, mainly due to lack of space, or not wanting to bolt on a knee buster.
and to answer the original question, I've only used 70cm once just to say I did.. but I'm on two 2m channels all the time.
82 fj40, 99 uzj100, 06 gx470
05 525EXC, 01 XT225, 07 TTR90, 07 CRF50