540p is fine for handheld. Hopefully it hits 720p when docked.
Very very impressive, for as much as I'm a, "put everything on Switch!!" guy, I think this is one that I'd opt for on PS4, even if I hadn't already played it.
Portable play is something the Switch version has over every other version, and they should sell it based on that, but FPS is one genre that I really don't prefer to play handheld.