In reply to Whitters:
1. The one pocket of the FL, to me, is cutting the features down a bit too much. The AR is a tougher jacket with reinforced areas on the shoulders etc and the two pockets are much more usable imo.
2. The Lhotse is a great jacket, great fit (for me) and good hood. Maybe look at the Tupilak Jacket as well (same fit, bigger hood if using a helmet a lot and just two pockets).
3. Mountain Hardwear Dry Q Elite fabric is basically rebranded event. Whether you think this is a good thing regarding durability is up for debate, personally I've had no problems with event. I have no other comments on this jacket as I haven't seen or worn one.
4. The Latok is a good tough jacket, that sizes big because it's designed for layers. However its a bit heavy, and who really needs all them pockets!?
Regarding the zips they all use the YKK Aquaguard Vislon zip (for the main zip at least), which is a lot more durable and water resistant than the older style YKK water resistant zips that some of these jackets use on the pockets (except the Lhotse). However, they are still water resistant, not proof, so they will all have a storm flap behind. Personally I've had no leakage from this new type of zip.
Personally, for me, all of these jackets would be too heavy and bulky to be carrying around in the summer (possible exception of the Arcteryx Alpha FL). They all seem great options for Scottish winter to me though.