That is the EXACT list of bikes I was considering, with the exception of the 1200 GS ADV (I was considering the standard model).
BMW - sparse dealer network, expensive everything, final drive issues, no local shop,
Triumph Explorer - On paper it appeared to be the perfect bike for me. No plans for serious off-roading so didn't care about limited capability. Brand new and untested engine, bad experience with local shop (Honda dealer I've dealt with in the past), sparse dealer network, at $15,700 a good value but still $2,000 more than the Tenere, limited availability.
Ducati MS1200 - Beautiful, comfortable, stupid fast, but - chain drive, sparse dealer network, same local dealer as Triumph, more expensive everything than the BMW, a stupid keyless start that can strand you with no manual override, a lot of electronic wizardry (suspension, 4 modes, etc) to go tits up on you, legendary Ducati reliability on a bike I want to take to the middle of nowhere? Ummm...no.
Super Tenere - I rode it, next weekend I bought it, five weeks later couldn't be happier with my decision... Plus I've got major coin I saved over the other bikes to farkle the nuts off of it and make it perfect for me. Simple. Now I try and find time to ::021::