Strange isn't it. For me it's the fit, an XL top and L trousers just fit perfectly and make you feel like getting out and doing something.
Same here, Michael. I'm a short-arse and a bit lardy to boot - hardly the kind of physique that outdoor clothing manufacturers have in mind when designing garments - yet Montane's medium-sized upper-body clothes seem almost tailor-made for me. They're not too long in the arms, a good fit across the chest and have just enough allowance to accommodate my (ahem) ample waist.
Even the Extreme smock (must stop going on about it, I know) which is not very stretchy is a good, if snug, fit. Just pulling it on in the car park before walks on Dartmoor a couple of weeks ago made me want to stay out all day. Good kit makes me work harder, just to see if it works under harsher conditions.