I have offroaded a 650GS (normal version) for a day in some quite tricky stuff they are ok, in fact fine. Engines usually good (Rotax). They will tour as well. A DRZ would be a better laner but if you want to do reasonable distances something with a bit of road abiltiy is an advantage, although the DR isnt bad for that at all. Its all well and good thinking of the little small engined traillies but you have to think about how much road work, on bigger rides it can be considerable. The 12GS is a great allrounder but a pig when it gets knarley unless you are a big person. Many people that get into greenlaning/trails in reverse, ie starting with a GS then get a DRZ, TTR etc etc.
Why not flog the SV and get an 1150 or even better prob 1100GS, or maybe a used V-strom. If you get to 5k you should find a good but a little less loved 12GS possibly (with a few miles and so any issues sorted). Then you will be able to play with your mate road or trail? You may not look back
