The mistake I made was buying budget outdoor equipment. I've done it before with poor results, but for some reason I was tempted by these "waterproof" trousers - never again. So what's wrong with them? Three things:
1) They're not waterproof. They slowly leak in particularly heavy rain, and you get a wet bum on a bike in light rain.
2) They don't let moisture escape. I've scoffed at so-called 'breathable' fabrics in the past, but you get almost as wet wearing these trousers as you would if you were wearing denim. It gives me a rash on my legs after several hours' use because of the damp.
3) The (boot) ends are fixed; and by that I mean they aren't zip/buttoned. Ever tried taking off your boots whilst outside in the pouring rain to try and get your waterproof trousers on? If you cant fit them OVER your boots whilst wearing them, what's the point? I'm not going to go around all damn day in waterproofs.
So, in conclusion, I recommend going to an outdoor store (Millets, Blacks, Tiso etc) amd talking with a member of staff. Get some good quality trousers that fit; and make sure you can get them on whilst wearing your footwear of choice. If you buy cheap, you buy twice!