I realize this thread is somewhat old, but I just noticed it and wanted to add a little something.
I've been using 260Q balloons as shock boots for about 3 years now but I do it a little different so they have smoother action and less bunching on compression! I pinch the balloon with my thumb and forefinger about an inch or so from the end. I hold the open end over the tip of my air compressor nozzle and inflate a small portion of the balloon as big as it can get.
The inflated area stays stretched when you let the air out and the part below where you pinch stays nice and tight to the shock end! I get 4+ shock boots out of each balloon!
For those that were making a big deal out of not getting full compression....if at any point during your race your shocks become fully compressed, you aren't going very fast because your chassis is dragging on the ground
