They are quite different, can you elaborate on your reasoning?

Depends on your needs. I have both in my mesh, as it is quite a big place.
XE200 has more coverage on signal, but not a dedicated backhaul on 6GZ
BE85 is giving the wifi7 and dedicated backhaul.
If you have many devices that can support Wi-Fi7 and do not want to change it again in a few years, it is worth the investment if you do not have a huge surface.
if you are happy with wifi6 and a lot of space, go for XE200

i would go for be85 as it is future proof and you can create a backhall, i.e. connection between the two devices via wifi 7. these frequencies are currently not occupied by anyone, meaning your neighbourhood, and therefore perfect for a connection.