2X10 setup?

Im looking into changing my front cranks to a 2 ring set up.

What do people use/recommend for the sizing?

26-38 or 28-40?

My biggest cog on the back is a 36.

depends on how fit you are but at the moment im using a 38-24 with a 36 on the back and loving the setup. It is on a 30lb 6" all mountain machine so if it was on a skinny bike id go with the 28-40

Fittness wouldnt/shouldnt :) be a problem.
It will be going on to a 140mm full suspension xc bike. Its got a 3 ring setup at the moment but i only use 2 if even that and ive heard quite good reviews on the 2 ring setup.
I was leaning towards the 28-40 for the bigger top ring.

If fitness isnt a problem , then go 1 x 10 , 1 x 32 tooth on the front save yourself the weight , trouble , expence of extra sprockets and shifter and derailer ! Rode ss ( fround upon here but great fun but not that hard ) most of this year and you would be amazed what you can climb when you have to . I do think a 1 x 10 or 1 x 9 setup on a 140 trail bike is a good set up .

you can always count on the Cork feckers to cause a row..I heard they were the ones who started the Blast !!

No Richie, we didn't start it but an awful lot of us did ride it and had a right "BLAST", we will miss it, pity.

oh I dont think its going away that easy ! but thanks