Have used Wiggle for four orders now. Orders have always arrived promptly - sometimes items are delayed for a week or so but in the meantime they send what is in stock.
Fantastic website - with useful 'rank by price' feature - check it out on a regular basis to get some good bargains!
Have also used 'On the Run' - forget it! The order took 6 weeks and two phone calls from me before they got it delivered!!!
Sweatshop comes a close second to Wiggle - I use both now for what I want. What one of them doesn't have, the other will.
Overall I reckon Wiggle and Sweatshop are the best on the web - delivery usually a couple of days after you place an internet order! Wiggle does give you a healthy 5%/10% discount but Sweatshop does have a good selection of heavily discounted 'sale' stock.
Havn't had any Wiggle sweeties either! Are they an urban myth???