In reply to Os_878:
LT is an excellent jacket and far more suited to your requirements. Fit is also better than the MX. It is now my go to soft shell. Its lightweight, breathable, can layer exceptionally well (for me I use an Atom LT underneath) and is pretty durable. I also like its slightly longer cut, fits much better under the harness and the 3 pockets are more than enough (Ok I will admit a sleeve pocket would have been nice). Plus its relatively in-expensive (By Arc'teryx standards) in comparison to the other two.
The SL is incredibly lightweight, makes for an excellent summer alpine or long multipitch jacket. It's limited by its complete lack of insulation and lightweight fabrics, but its breathability is excellent. Whilst it is a very nice piece it wont do so well through the winter season as it is just too thin. Although the fact the sleeves can be rolled up is a super nice unexpected feature!
The MX I've lost a lo of faith in, the older powershield versions were much nicer, more durable and had a better fit. The new Fortius material is I feel stretchier and more breathable, but also much less durable. I find it wets out faster, is not as wind-proof and the fit isn't great when compared with older models and I've noticed that the cut is rather inconsistent in newer models... As is build quality. But that aside, as a winter climbing jacket it excels over both it does have long arms, the cuffs are far more compatible with gloves than the LT and it is much warmer and cosier to wear on a frigid day, but I would still take the Venta MX (no good in the UK) over all others for winter work.
