I need some recommendations on what to use to keep the XR6's leather nice and schmick.. don't really mind if it costs a lot of money, so long as it's decent and won't have the leather going crap in a couple years time.

Try these people http://www.uticolor.com.au/index.htm

Go to a saddlery and get some good dubin. Nothing works better to soften and keep leather hydrated. I had a leather jacket that was hard as plywood. Started rubbing dubin in every night for a week. After one week it was soft like a chamois. Can get a bit 'greasy' if you use too much until the leather absorbs it all.

You would probably only need to treat once every 6 months for the rears (if they're not used much) and every month for the fronts. It will never crack or anything then.

I have always used dubbin.