I took a break for a while, sold my Libra Special and Razors (due to transport limitations never used em). I got a car now and work down at Hastings (less than 1/2 an hour from Camber) and so ran out and bought a flexdeck yesterday!
I only have a 2.1m Little Devil at the moment but to be honest some of my best runs in the buggy were with that kite (I love working it). Hopefully the wind will play ball when all the happy campers go home!!!
I cant recommend the 2.1m LD highly enough it has the extra stabillity required on those strong and gusty days. I think a 2.1 LD and a 3.5 Razor is a better combination, but then I would
A ruler will work, the circumference is pi times the diameter!
Sit in the buggy and get someone to measure from the center of the wheel to the floor and times that by 6.28.
Allthough the method you describe is easier and you dont need a calculator
looking at your kit I assume its for buggying? Anything will be better than a large blade, they have too much lift!
I would recommend a Little Devil if you want an easy ride or a Razor if you want a rewarding and fast ride. There are many other options too: Libra Bora, Airea Raptor and PKD Century to name a few.