I have now jumped on the vintage Suntour bandwagon. I can't help but love the weight feel and look of the Suntour Cycle derailleur. It is clearly a better shifting lighter derailleur than the old Campagnolo record of the same era. Even the Suntour clamp on shifters are better.
My uncle gave me a beat up old motobecane and I noticed it had Suntour clamp on thumb shifters that had white plastic covers like the Campy design. The main difference is the action was a helluva lot less clunky. I will be getting rid of my Campy shifters...soon.
I sure am glad Suntour parts are still a good value today.