Well I know it's a complicate question and point but it's a very common topic on beaches so let's try to have some better feedbacks!
The optimum: sail and mast from the same brand (and same year!)
But you know better than me that optimum is in most cases very distant from reality!
I found an old topic here
So, let's go ahead!
Waiting for the moment all brands would precisely indicate their bend curve, let's make a compatibility list!!
For instance, as starting point. I got a north viper aero 460 mast, how would it go with Naish sails?