Well, I just bought one of these on Amazon with a 10% off coupon brought it to $421.72. That's just too good of a deal to pass up and take a chance on. Delivery (Jan 21 - Feb 11). So there is the rub, It's coming from china on the slow boat.
The recent teardown of chinese battery packs have shown that the cells are good but that the connections may need some attention. I plan on pulling the cover off and looking at things and making adjustments. Worst case I have to rebuild the pack or possibly harvest the cells and make my own which I would still be ahead on the cost of the cells alone.
This is for a enclosed v nose trailer that I'm putting a bunk and small kitchen with a 12v fridge, led lights, TV, Stereo, Inverter for power tools. Think mini garage toyhauler.