I would still recommend both, but I would see if you can get someone who knows your band decently to play test them and give you some perspective on the current state of the instruments and how they will fit your ensemble.

I haven't done a lot of in depth testing on different trumpets and have mostly played on my Xeno and just stuck with it.

In general I have heard from other trumpet players that the tone quality between them is really the biggest thing they notice. Bach Strads tend to play brighter and a little more open than your Yamaha Xenos. The Xenos tend to have a darker tone and I personally find that partial changes tend to slot a little easier, but that's more of a personal preference and experience.

Either would still be a good addition to your inventory as long as they are taken care of.