Wore nothing but 5.11 for three months in Afhganistan:
Taclite Pro trousers - much better than the standard canvas - more comfortable and easier to wash
Trainer belt and BDU belt - both work very well, and don't curl
Tactical shirts - sent them home after their first encounter with Camp Bastion laundry. They came back rolled in tightly-creased balls and no amount of ironing would get the creases out. They work very well if you wash them cool or cold and then hang them up on a hanger, but the laundry wash and dry everything at the temperature of magma. They improve with age and washing - I've had some over 5 years and they are now nicely soft.
Tactical polo shirts - excellent
HRT Advance boots - very comfortable and the side zip was very useful when on call
Tac NFO gloves - good fit and hard wearing
Boonie hat - brim needed tailoring to avoid the 'hat, ridiculous' look sported by the US Marines
Muscle mapping t-shirts - comfortable, especially when wearing body armour. Failed to give me the streamlined look I was hoping for.
Rush 24 daysack - excellent bit of kit.
All my kit stood up very well to the environment and being worn and washed often (laundry every other day). 5.11 is very popular with US contractors - if I'd grown a goatee and a beer belly and festooned myself with unnecessary weaponry I'd have fitted right in!