43 Air School are probably the best - they do training (or used to) for Kenyan Airways, South African Airways, Police force choppers, Cityjet in Ireland...
Big school, own airfield and own aircraft maintenance facilities.
More expensive than other schools but you'll be doing a fully integrated course which is more appealing to airlines than the modular route if thats the way you're headed and you'll find airlines in the UK and Europe have heard of them which helps when your cv is on the pile.