I have shorai on the R1. Never had a issue with it. From what I hear they can be a little cold sensitive but living in Florida that's a non issue. When the oem battery croaks I'll probably get one for the R3.
The bike charging system is a non-issue. What you have to watch out for is battery tenders compatible for your battery - - two main reasons: the right one will maximize life of the battery, the wrong one will not. Do not jump start (quick charge) these with a system designed for car batteries - they can grenade - seen it happen.
That said, stock battery is just over 6 lb. A Ballistic 4 cell is less than a pound. My local bike shop has the correct balancer/tender and takes all his customers' batteries during the winter at no charge, so I didn't have to get a tender. They are a little more cold-sensitive than lead-acid.