Anybody here use them? Have heard enough things about the, that I got curious, and picked up a box of 5.

Thing is, I don't see any point wasting them on my 1 hour+6 lpas races. I'll be doing a 4.5 hour group ride with 5 other guys on Sunday (and I have the feeling i'll be doing more than my fair share of work). Perhaps that's the place to try it for the first time?

Suggestions from 'users'?