Oldham is the L8 match on this exchange. I am heading in the opposite direction to do London NZ-Stevenage.
Oldham will be a strong enough side with forwards who will get stuck in! They can be a bit vocal so put a lid on it early on. Massive in-goal area, only beaten by Vale of Lune in my experience.
Can't tell you much about St Edwards as their home matches are covered by Liverpool society so we only get to see them on visits to Manchester and I have not had the pleasure yet.
Oldham will be a couple of degrees colder than everywhere else in the country (or it just seems that way). But they do still have a big communal bath (if that's your thing).
Enjoy.