Starting FO pay as a year one FO (about a year after starting your upgrade from SO is a take home of around £7300. This is on a normal non-expat contract with no housing.
Seniority-based pay scale goes up gently, take home as a fresh skipper around £11500 net.
Similar number of pay points to BA.
Not that it's the only consideration, but the money in the UK isn't great.