I am just completing my build of the XTREME CF frame for the HBK2.
I must say, I am impressed by the design. It offers a alot of advantages:
1) Adjustable servo mounts (for just about any servo - Stock Esky 8g, HS55, HS65 and others).
2) You can get to the belt idler gears from the top, no more trying to squeze them in through the bottom where the frame interferes
3) The idler gears are on an adjustable slide, allowing for more belt tension adjustment!
4) Getting at the motor screws is a breeze!
5) Just about any motor will fit now, no plastic lip to cut to fit some motors!
6) Nice gyro mount tray!
7) Much better holding of the tail boom, it even has the key that allows the boom not to rotate


I have learned that you MUST use blue locktite on all the screws! Dont ask me how I figured that one out.

I'll break out a new one and weigh it and the stock one, and post the results.

Michael