MrFunnyWobbl: Backspin literally increases the revolutions per minute at which the ball spins. The resulting increase in spin allows the wind to affect the ball more and hence on crosswinds a misding into the wind will be seriously penalized due to this.
This is very true, especially with high-trajectory clubs.
I once asked a similar question what Sammerson is asking, mine regarding TaylorMade R15 irons, though.
Solarflares provided an outstanding answer with every detail of mapped distances including first-bounce points, rolls and whole nine yards, but then for an unknown reason, he deleted every single reply he had given before I was able to copy and elaborate them... :-(
Now that I'm playing with both R15 and NIKE Vapor, I can say that their distances don't differ that much except for R15 3 iron being noticeably more elastic.
Anyway, some yardage charts of clubs are available in my blog so feel free to use them as you want. As I mentioned it there, I got them from somewhere else, but don't remember exactly where so unfortunately I cannot credit the original author(s).
I hope it helps a bit, Sammerson.
Regards,
Simon