I have tried quite a few of the big ones and struggle to understand how they can get it so wrong.
Bourne Sports - even writing it gives me the shivers. Ordered shorts off the web, chased them up twice by phone when they did arrive which was after 4 weeks wrong size and colour. Never used them since. Refunded item only not postage - even though it was their fault.
Sportsshoes Unlimited - ordered some shoes, they got the post code wrong and the package went astray. Had a hell of a job persuading them i never received the things. Felt like i was a bit of an inconvenience to them and it would have been better if i had simply gone elsewhere.
Up & Running - Hyde Cheshire. Brilliant very helpful, nothing is ever too much trouble. Cheap.