Having broken my 460 mast earlier this year I've been using a NP supersonic 7.4 on my 490 mast and you know what, its heaps better to sail on the 490 even with 7-8cm of mast showing at the base. The sail seems a little more gutsy through the lulls and still twists off nicely in the gusts. So I'm wondering if the extra stiffness IMCS 28 instead of 25 is a better match to my 92kg weight?

I read cribbys article with Dave White (130kg) who sails a couple of metre bigger sail with no downhaul and kicks arse.
www.guycribb.com/userfiles/documents/HavingItLarge.pdf
I get the feeling I've been too focussed on the numbers written on the sail.