In reply to Penguin16:
I got a pair of the mid range TSL ones (I think from EMS) with the heel lock, but not the drop through heel.
Have used them on alpine winter trips and found them to be good allrounders.
Lightweight, and with effective points for use on patches on neve.
Well priced, but I suspect not as durable as the more expensive MSR in the long term.
I'm heavier than I'd like to be, and with a pack I made sure to get the correct size ones. In seem to recall that they are sized according to weight and gender.
Cost effective option.