one thing to bear in mind is that you are buying direct from a chinese bargain basement shop.
So don't expect any backup. ie: if it goes wrong make sure you'll be happy fixing it yourself.

Personally I'd buy one of these: http://wanhaousa.com/products/duplicator-i3-steel-frame

Still dirt cheap - but much better build quality than pretty much all the kits I've seen. Plus they've been around for a year or so now and they've ironed out all the initial issues.
uk shop selling same thing: http://creative3d.co.uk/wanhao-dupli...cysaAp-e8P8HAQ