I found the set-up Gayo has pointed to had a very different feeling than what I've run on my X - 6 before. The best way I can describe it is that it feels very front-leading instead of rear-following. That is, instead of driving the car by focusing on the rear end and where its going, I was able to put the front end of the car where I wanted it on the track and the rear end just followed along nicely. That's not to say the rear end lacked forward bite or washed out all the time - the whole car just drove very precisely. I think a large part of this feeling was the 20* blocks up front.
I did not have great success with the car on a more slippery track though and have since gone back to running with 30* blocks; in fact currently I'm very close to what Brian and Dan Griffin have been running (see the set-up page:
http://www.2wdrc.com/tech/SetupSheets.htm). We've found these set-ups develop exceptional traction on lower-bite surfaces but still feel pretty good when the grip levels come up.
BTW, since the CRCRC race we here in the states have been running our Squared cars "light" - no weight in the car except for 20 to 50 grams up front. Most of our cars are around 65% rear weight, 1550 total.