Youll be fine without a subaru filter, if youre using it long enough that it creates the pressure to go into bypass you need to stop being cheap and replace the filter each change and change more often.
I use Bosch Long Life D3300 oil filters and Rotella T6 5w40, gonna see how Motul 8100 5w40 does in comparison.
Avoid 5w30s most of them sheer to a 20 weight by the end of the change interval if you drive your car like its meant to be.
I've never had issues, and I oil test my car a few times a year.