Hi Maidup,
I'm with the RAC. I've only needed to call them to my car twice in ten years (both times a snapped clutch cable) as I carry a toolbox and emergency kit and usually sort any minor problems out beside the road. I have called the RAC about three times when I've been with someone else who broke down as they cover me and any car I'm in at the time.
However, my problem with the RAC is their renewal procedure. Two years ago I was paying about £90 a year for three different features. They sent me a renewal of £141, despite me not having called them out! I rang them to say I was leaving - and they immediately reduced it to £82! Last month they send me a renewal price of £121 - despite me not having called them out again! When I again called them to say I was leaving they wittered on about increased fuel prices - then reduced it back to £82! What next year I wonder? The RAC have been very quick and reliable when I called them, but just be careful with their pricing.
My father's with Green Flag and he had no end of trouble with his Astra until he recently bought another car. Green Flag kept coming out and he seemed pleased with their speed and service (despite the fact no mechanic working for them ever identified the running fault). Green Flag use local garages under contract rather than employ their own staff.
I was with the AA years ago but they left me stranded on the M40 for 6 and a half hours in the middle of winter one night! At the time they had a policy of 'stranded women first' and I kept slipping back down the list as women kept calling in. Despite the fact I was dangerously parked on the hard shoulder, several police patrols had called them and I had a van of gypsies turn up at one point, they still left me! They soon abandoned that idea of women first as so many men like me told them to get stuffed and left, but I've never been back to the AA. I only hear good reports about them now though.
Good luck.