Had a look on the various sites and it looks interesting (the tail dragging version looks more natural) and was wondering if anyone has or has had direct experience of the S6
Popular aircraft world-wide as I'm sure you have discovered.
Our club (of 150 members or so) in NZ operates two S6, both 582 with pre-sewn skins off grass (and sometimes less improved farm strips). They have proven to be strong and reliable training aircraft.
Both aircraft are now tricycle, we previously had one as a tail dragger.
Short story is that after a number of mishaps and we thought new training regimes, new gear configuration, larger wheels, better brakes etc had "sorted out the problem", a real doozy of a on-it's-back sealed the deal and the insurance pay-out had us rebuild as a trike. Not saying that a tail dragger S6 is a bad thing necessarily, it wasn't a death trap, just that our specific tail dragger S6 did not prove to be a viable platform for continued training of low time pilots. The pilot was uninjured, thanks to the strength of the design.
Main skins have lived to about 1500 hours, the aircraft are stored in a nice dark hangar even between flights when sensible, don't even think about storing with any UV exposure or they will perish far too quickly.
We had a main gear leg fail at about 1200 hours, in a manner in which it was not obvious until the aircraft was airborne, and the gear leg was hanging from the brake cable. The aircraft was not otherwise damaged in it's bicycle landing however. We had a destructive analysis performed on the surviving leg and it basically came down to metal fatigue. Lesson: it's pretty cheap insurance to replace the main gear legs every few hundred hours.
I won't discuss engine matters really because that's the same whatever aircraft. As mentioned we use the Rotax 582 but are considering moving to 912 eventually, but purely from a TBO stand point (rebuilding an engine every 300 odd hours is a bit of a drag).
In short, no particular show stopping vices, strong construction, stands up to the rigors of training pretty well.