I have soldered an XM1541 cable to connect the commodore's disk drive to a pc's paralell port and guess what, transferring d64 images to and fro workes fine with opencmb! So I have been enjoying cybertracker, NinjaTracker and Sadotracker on the real thing! I find cybertracker is the easiest to use, Ninja and Sado are a bit mysterious to me.
One thing concerning the left shift key in cybertracker, implementing correct shift-lock detection in Frodo DS should suffice to make graphical waveform and envelope editing in cybertracker possible.
Unfortunately the C64s HF modulator seems to be somewhat damaged, the picture I get when connecting it to my pc's tv card is a bit shakey, but anyhow, SID is doing well. It's quite interesting to compare an emulator to the real thing side by side.