My experience of the dealerships in the North West has been pretty positive so far. I actually don't think the servicing costs are that unreasonable either and, unlike a local independent I tried last year, I haven't experienced any recommendations of unnecessary work.
Like Downsizer I have experience of Swansway Honda in Stretford (where I bought a car but haven't used their service department), Swansway Honda in Stockport where I have both bought a car and had it serviced and, since our move back to Warrington I have found Holdsworth Honda (formerly Lightcliffe Honda) to be very reasonable as well.