Mike Davis wrote (see)

the frames geometry is probably more important than the material.

Take out "probably" and you're there  

Well a frame with an 84° head angle and 69° seat tube and downward sloping chain stays would be a dog to ride whatever it were made of - unless it were a BMX of course. 

Well dilema, still trying to find a hardtail frame to suit 100m forks, nearly bought a new bike today a Spesh Hardrock for £250 sell all the bits on Ebay and just bolt on all the bits I've got lying around.

But bought these and this instead

so no nearer buying a frame 

Not realy Mike, I rode a Diamondback Ascent EX for 10 years [Steel double butted True Taper Lite] and did most things I do today on My FSR Pro.

In fact still use the DB for work.

Just want something that climbs well and is good for single track stuff and is not to pricey

Drifting towards the on-one Scandal at the moment  but might even go for this

Main use will be winter and for when my FSR is on its total strip down service 

Buy the On-One: you know you want to.

Seriously though, I built mine up as a winter bike due to it's relative cheapness, the ability to run full length cable outers and the fact that the ride doesn't match the price tag.  The Scandal I rode a while back was even better. 

look at the inbred vs 456 post, and buy that guys inbred, its designed for a 80-100mm fork and of course everyone (nobby included ) love on-ones so you'll keep the masses happy

edit: added the link to the post