Agree pax b - Have used BA many times long haul in economy for holidays simply because they do non-stop to the booked destination. The service has generally been good so can't complain. I'd rather spend the extra on upgrading the holiday accommodation than upgrading cabin on the flight.
Their long haul business product which I've used is fine with the added bonus of Exec Club benefits.
Planning to do short haul domestic for business in the Autumn and Gatwick with EZY is the obvious choice with it being my nearest airport but the timings from Gatwick are not business friendly so BA from Heathrow it's likely to be with much increased frequency with timings suiting my needs.