I have been using a lithium battery in one shape or form since 2006. Currently have Shorai batteries in my Panigale 2012 1199S & 2011 675R daytona, both have never been on a tender and both batteries are over 6 years old, and so far have proven to be amazing. The 1199S Does seem to not start as fast as she once did in the colder days, if the bike has sat, but it always fires up.
So some pretty impressive stuff if you ask me. Some have had not nearly as good experiences, batteries that were DOA, and fizzled out after a few rides.