I had a 92 k75rt and it was a great bike, but it had some electrical issues, two I fixed, the other haunted the bike til I sold it in 2001. The headlight would flicker for no apparent reason, I'm sure it was a ground but never found it. One problem I fixed was in the left turn/headlight switch that can only be bought as an assembly. You can tell if they are going bad, they start to feel mushy instead of a "crisp" click upon tuning the signals on and off.
It handled pretty well, although newer bikes will put it to shame. I put some long hours on that bike and other than having to add a Corbon seat, it was comfortable.
Edit to fix and add stuff my phone would let me do.
My buddy had a K100LT and he had handling issues, Google "hinged in the middle" with BMW K100LT and see what comes up. I rode it on some twisties and understood exactly what he meant. I don't know if that characteristic transferred into the smaller brother (I don't know if they made an LT version of the 75, but as I said, my K75RT rode and handled great. Smooth bike.