I started a thread on this a while back,
this post contains most of the info that I found. I did the
Gruyère Cycling Tour last year. It was possibly the most fun I ever had riding a bike. I think there were 1500 people all together, although most did the middle distance, and only 200 or so did the full distance that I did (165km with about 3000m of climbing over four passes). It starts and finished in the town of Bulle, which is 2 hours by train from Zurich.
When you say the "Alpen classic in Andermatt" do you mean the
Alpenbrevet? I'm hoping to do that this year, though probably the "Classic" version, and not the insane "Challenge" version.
I did the Lac Leman tour last year ('06), but missed it this year ('07) because of a friends' wedding. This was the first year for the mountain version, so I've not done that yet, although I've done virtually all of the course in sections on various solo rides. Where there many people doing the mountain version?