Kr2 question

My local SF dealer has the KR2 kit in stock for a pretty good price. I Am looking for a rechargeable light and I already have a 6P. Is the kit any good, and is the B65 battery only 4.8V? If so, how does it run the p60 lamp assembly? Or is a better idea to just get the strion? I am thinking that the kr2 kit would be great because I could always get a KL5 head for the light etc etc. Also, does the extender that comes with the KR2 kit allow me to use 3 cr123a's and a p90/91 LA? You guys have an awesome forum going here, many thanks for all the useful information!