Thanks for your feedback..
The best thing in these cases would be test them but it's always very difficoult.
Anyway I don't need them soon so I got plenty of time to decide!
Last thing: which is the RAM downhaul tension? Is it very high?
I'm interested in this point because I'll probably use this sail with the extender (I'm about 70kg so i whould work..) but I really don't want to damage my viper aero which is not very indicated with "race" sails..