There's a range report on the G29 here:
http://www.10mmtalk.com/index.php?showtopic=8424
I wish I could afford ammo for a 10mm, a G20 would probably be my next sidearm.
From what I understand the 10mm is kind of a "ballistic twin" to the .357 Mag. Also, a guy named Mike (I think) at Double Tap Ammo has done a lot to resurrect it. And it's supposed to be uber-versatile to hand load for.