you buy a GS for a comfy-even two up-, tall, long distance touring experience, but something that won't be a complete pig to filter in town or park, something that will also take you for a bit of green laning/exploring bits and bobs where a full 400kg tourer would struggle even more so. You don't buy a GS for pure dirt and rough as they are too heavy (by about 100kg). Weight makes them almost as useless as a stree tbike on the rough stuff, their only marginal saviour being knobblie tyres and softish suspension, but enduro bikes they most certainly are not.
But if you are telling me you will be transforming your GS for green laning only (without much experience or any motocrosing mileage under you) then good luck! You got a seriously unhelpful bike under your inexperienced self. The picture above with the dumped GS in the stream could be you. No crash bars will help you. These are for one time crashes only to protect the bke from trashing itself entirely. In "green laning" even people with a few amateur motocrossing miles and racing under them (like me) tend to fall quite a bit. Sand or mud riding, you may fall 3-5 times in a single fun day.... Your GS will fall apart before the day is out (and it will be costlier to fix than a cheapo drz)
Bottom line: +2 with opinions above. Keep your GS as your "good" bike for touring and going places. Buy a crapduro - any old roadworthy rotter will do, £1500 XT600, DRZs, even proper enduros like XR400, KTMs etc, any light single cylinder bike with a bit of poke (key: keep bike weight under the 150kg mark ideally closer to 110-120kg like the Honda XR4 rather than the lardy 225 dry weight of the GS) to do and learn everything about green laning with a smile in your face. These bike are light so you get less bulk burrying you when under them, they are also light enough that when crashing they tend to sustain less damage. (if you are a skier and you go skiing with your kids you will understand it better: the young ones crash on the slopes and seem to bounce right off. We tend to end up in hospital

)
If on the other hand, you really really want to to get involved with a GS, try and get some experience with someone else's bike first- The welsh BMW course organised by BMW is a good if expensive start...
Good luck, you been warned....