I've got 08 and 18 1200 GS both standard. 18 1200 GS is loads faster that 08 (08 has over 150 000 miles mind). I like both bikes, but if you want more poke test ride an LC. Plenty of power there.
Mine has been on for a year now. I'll never go back the original!
Definitely an improvement in every respect.
ps. I still these headlamps on Alibaba, along with the mkii version (which is cheaper - and I think a true swap) but this mki version looks great. But you do need a torx key to adjust the beam... which in reality is not often at all.
Really interesting I'm actually looking at the single cam hexhead's or an 1150 had loads of grief with my old lc gsa so a little weary of them although it still ranks amongst one of the best riding bikes I've ever had.