In reply to Colin Scotchford:
They're really good. When out in the states the baffolds blew and I ended up with a beach ball in the middle of the mat, they were great in replacing it. Didn't have the model I had in stock so sent me a much better and more expensive one, free of charge.
Initially wanted me to send them a picture of the broken one with a knife in before sending a replacement out but when I explained I was thru-hiking and would need it in the interim, they were fine about it.
Also met someone who contacted them after a 9yo semi-self-inflating mat had a fault with it's valve. Again, brand new Prolite free of charge.
I'd always recommend brands like thermarest and darn tough for this kind of service.