I seem to think I've tumble dried Benjamin's Lovebums wrap that has Bob the Builder on it, and still pretty hopeless - gets totally soaked quite quickly. Maybe their wraps with cotton outers just don't hold up? I have a couple of solid/girly coloured Lovebums, which are more of a normal PUL type fabric (rather than the cotton) and they work just fine, and actually look like they're more used. So I've begun to think the Bob wrap might just be for teddy bears to wear, rather than functioning as a wrap.
But then again, I'm no expert on these things....just seems I don't get on very well with cotton/PUL backed wraps/nappies, etc!