Neale, its actually not too bad off the bench, I put about 40 through it today, all bench work, but it does tend to bounce around a bit so a good firm hold is needed.
I was pretty inpressed with the velocities myself, there is a post on the AR forum about 416 Taylor loads, most of those guys are using around 72 of RL 15 and getting about 2350 fps, so I think I'm near the money as well.
I'll just have to keep playing though!