I am going to buy new/secondhand two race sails.
Considering either Gaastra GTX 2011 7.0 and 8.0 or Severne Reflex III 7.0 and 7.8.

Because very attractive price on Gaastra that could be my first choice, but because I never had a chance to use any, wonder if Gaastra Gtx offer similar performance to proven on our waters Severne ?

If Gaastra also has such strict requirements regarding compatible mast ?

Main consideration will be slalom race performance.