I'm really pleased they planned all along to replace the wine and, in fact, did so! It's so rare that these stories have a happy ending.
That being said, I don't like to be a downer, but think of the angst their action has caused, because they didn't leave a note/email/etc. about their plan. And, the fact remains that they did drink something that was wrapped up and set aside a bit, apparently without researching it beforehand. The fact that they replaced it is great and makes their actions overall a whole lot better, don't get me wrong. But I might think to myself that they and I have different boundaries when it comes to being in someone's home, and maybe I'm not comfortable with them being in my home unsupervised any longer, just because of that.
I mean, they didn't rush to have the wine replaced by the time the OP got home, for example, or make sure to communicate their plan with her--what if next time they borrowed something the OP really needed right away? Or, since they didn't research the item they borrowed before consuming it (which they might have learned from now, granted), what if next time they consumed something that couldn't
be replaced, or that they couldn't afford to replace? (Even with the wine they went with/had to go with a different year, so that's not an exact replacement.) To me--knowing nothing else about this couple except what's in this thread--it would make me wary of setting up this same situation again.
Definitely not a relationship
-ender, but maybe I would just say to myself, "Okay, these aren't the people I'm going to ask to check on my house again while I'm gone. We'll do other things as friends."