I purchased this exact kit from eBay.Its been awhile so I'm not sure of how long it took for delivery.This kit was pretty easy to put together.im running this kit with Sla battery pack and I'm impressed.Cant wait to upgrade to lipo4.
I am considering the purchase of one of those kits but their lack of english and support leaves me wanting to shop elsewhere.
Systems with components from different companies will be less expensive, but more challenging to install than turn key units from ebikes ca, ebikekit, dillenger ... I purchased a 350w, 36V, 10 ah kit from Dillenger for my first attempt at an ebike and installation was easy. That said, a 1000w, 48V kit from ebay plus some LiPO batteries from Hobby King wouldn't have been impossible to put on my bike and will probably be next in line.