I always prefer wireguard as OpenVPN never works stable on port 443 here (in a censorship area). But importing wireguard settings of Mullvad (builtin feature of B1300) hardly works on my B1300 and mostly fails. Sometimes I do a workaround for it, 1st I use OpenVPN and then I import Wireguard settings using the GUI.
But this workaround is pain in butt, as I do it many many times before I succeed. Mostly as OpenVPN doesn’t work stable I fail to import wiregaurd. I do it 100 times before I get lucky.
Updating firmware is fine but thought of resetting it after an update is a nightmare.