I have been wanting a Valk Interstate for some time. Rode a couple and both had growly sounding trannies. Other than that, nice riding bikes and plenty of power. Yes, they have the same drive train as the pre-2001 Wings. I'm currently looking at a 2001 out in Winnipeg. Only has 24,000 miles on it. From my limited knowledge, the 1999 has some issues that were cured with the 2000 & up model. I think they were partially dropped due to the change in engine for the Wing so they revamped it and called it a Rune ... IMHO, that was the "rune" of the Valk (ruin ... pun intended)
Almost bought a real sweet 2000 Valk Interstate a few years ago just before I bought the Wing. It was in Regina, SK. I was just about to hop on a plane and go get it when the guy called me to say he sold it to somebody local that had expressed interest before me. I was real choked. Brian (friesman) had checked it out for me and everything.
And now Honda has brought out a new version of the Valk ... what an ugly POS IMO. Their styling has really gone off the deep end I think.