I agree with you on the more points of failure, but they tout the multiple chargers as a simpler solution. Potato vs Potatoe.
As for the charge speed, I would always like to be able to charge as fast as possible, but that comes at a cost. Also, do I need to that fast of a charge? If I get 20 miles on a charge, I can probably go with a slower charger.
I do like the batteries that they use. They look to be comparable with the Leaf batteries.
Electric Car Parts has lots of batteries and BMS. They sell CALB 70ah for $92 each and I would want 16 ($1472 + shipping) instead of the 15 that Lithium Boost has in their packs.
You should put a total cost of your solution in the beginning of your thread. I can't wait for you to run your charge test. You should video it.