I have used Rohan gear for many years and still have some shirts and trousers that I bought about 20 years ago
I have to echo this - I have Rohan and TNF and Berghaus gear that is 20 years old and still going strong. I think it's more a case of changing modern gear due to fashion rather than need - much of it is superbly durable. I also wear a 30 year old silk thermal shirt though...