I tested the new Speed G 16/19 (300 gr) quite a lot the last 2 weeks.
I m currently playing the 2012 Radical Pro (630) and i actually had only 2 problems with the new Speed:
the different grip shape (not the traditional Head Grip-rather like Wilson)
the lack of mass (compared to the Radical Pro).
I was pretty happy about all other aspects of the Speed:
the Head guy told me to put 3 gr of lead on 12 and in the buttcap and it should work better...but i didnt try yet