I have Throttlemiester, which works really well. I had visions of touring on my S4, long since vanished.
Were I to do it again, I would get the throttlemiester that was the lesser weight as my handlebars stick out a little too much. The CRG lanesplitters get regularly banged back. Again, functionally, they work great. I can take my throttle hand off and do stretches on the freeway no problem. (Not in traffic, of course! )