I had one 100gr Rattray's tin, from the mid 90's, fail at the point where the metal had been scored for the pull top. The others have been OK so far. Stuff happens. It's a fact of cellaring. I don't worry about my round tins. So far they've held up. But most of those are older and stouter in construction.
Pre 2004 C&D tins were poor quality. By 2005 they were properly coating the interior, except at the solder joint, which improved things, but didn't guarantee anything. All of that has been bagged, and I'm glad I did that since some 16 oz C&D tins from 2010 and 2011 were corroding at that joint. Not all C&D blends corrode their tins, but I have a lot of Haddo's and that's one that does corrode tins.
Even some McClellands tins from the '90's fail, and those were better quality than C&D.
Ultimately we'll make our own decisions and get what we get.