I am preparing my invitations to be sent out, and my FI and I are using a wax seal with our monogram to seal the envelopes. I got the type of wax that is flexible, so the seal does not break when you open the envelope. The information about it said that this type is less likely to get damaged in the mail.
I sent 2 invitations early, to my sisters (one in-state, one out of state) to test the durability of the seals. The out of state one arrived in tact, but the in state one had just a tiny bit of the design chipped (although it was still very nice, and the monogram was readable).
My question is: have any of you sent invitations with seals (or received any), and did you deal with any damage? If so, do you have any advice on how to avoid it?
Thanks!
UPDATE: we paid an extra 20 cents per invite to get them hand canceled, and the wax seal arived fully in tact everywhere - even Germany! Totally worth a few extra bucks.

Thanks for the advice!