never used it to be honest, but I have only ever heard good things about it.
I tend to use whey for PWO and BCAA's (USN Glutamine and BCAA power punch) in the morning and throughout the day in between meals...
I may get some xtend eventually, but the USN stuff is quite a bit cheaper for me as my mate owns a supp shop and he doesnt stock the xtend
Carl.