I ride an 800SS that I really enjoy, but it has two deficiencies that are making me consider an ST4: I can't bring my wife along and I can't take week-long trips on it.
I was wondering what you all thought of the difference between the ST4's with the 916 engine vs the ones with the 996 engine? I'm considering a 2000 ST4, which has the smaller engine.
If you are riding an 800SS, you could even consider an ST2. A lot less maintenance, less HP but still a lot of fun.