I started flying from BHX orignally as it is closer to where I live and the car parking far, far cheaper than Heathrow or Gatwick.
The seating in Economy (Euro Traveller) is 3x3 as you all seem to know. I once sat on the left hand side of the aircraft in a row of 3 in club and was amazed at how narrow the seats seemed to be! Being 6 foot 1, I think I had to bend slightly to the right due to curvature of the fuselage! If I have to sit on that side I usually get the aisle seat if I have been unable to get the right hand side of the aircraft.
All in all I have been very surprised with BHX. BA has quite an impressive route network to most of the major cities in Europe which I need to fly too and its such a breeze to travel through compared to when I fly from Heathrow in particular.