Dixie Rebel,
I’ve tested a LOT of scopes for leaks over the decades, and while plenty have leaked I’ve yet to encounter one that leaked through the joints in 2-piece tube. All the scope manufacturers I’ve talked to (often during factory tours) seal the joint with some sort of compound.
I have also never seen a 2-piece tube break at a joint, and have even tested a few junker scopes by putting them in a vise and bending them. All bent, but the joints did not break.
More than one scope manufacturer has also told me that 1-piece tubes are great for advertising points, but make no practical difference otherwise. And all those manufacturers make both kinds of scopes.
All that said, I’d love to hear from anybody who’s had a 2-piece scope break or leak at the joint.
In all fairness, The scopes I have had fail were all reticle, turret or erector failures with one exception. That exception was a seal failure in the objective end of a Meopta.
All the other failures weren't worth sending back, and probably wouldn't be covered had I done so. The Meopta went back and was returned as a new scope with my choice of reticle in two weeks.