When the wing spar lets go the wings slap against the sides of the fuselage as opposed to the popular belief they clap overhead. I'm sure you knew that which is why you were asking.
There was a recent inflight breakup VH-WBZ. The ATSB report is available online.
As for the C210 reputation, why do you think it has such low Va and high cruise speed? It's the first thing you are briefed on when you fly it!
Wrong, wrong and wrong! This sort of stuff gets trotted out there and is given an airing every now and then. The fact of the matter is that the carry through structure is stronger than the struts bolted to the 206. I've been flying 210's for 30 years and have never been briefed by anyone on the wings going AWOL and I certainly havn't mentioned that to anyone whilst checking them out on the 210. Yes, a discussion on Va and the facts pertaining to that,but that's it.
Never been concerned about the wings coming off in an A36, PA32, SR22, likewise the 210.
The inflight breakup rate for the 210 as a percentage of the hours flown for the fleet isn't all that much different from the aircraft mentioned above.