A few things to consider:
If you're expecting a man to turn up with a van full of tools and the time to spend working on the fault, join the AA or RAC. Just don't expect that service after about 19:00 hours, because then you'll get the same contractors every other service uses.
Those contractors vary in ability. They're not paid very much, they're probably not as local as you think, margins are so tight they squeak and you are not their customer. Draw your own conclusions.
Those contractors work for most of the services, at the same time. They might have people sitting around waiting for work when your job comes in. They're much more likely to have several jobs lined up for each driver.
The bigger, older service providers that everyone has heard of do still care about their reputations, and at least try to give good service. The newer, smaller ones are a real crapshoot. Some them are oppsing useless - one I did work for was so bad that I never had a job that they didn't cause problems from the moment they sent us the job to reluctantly paying the invoice.
If your vehicle is covered by the manufacturer's warranty, then most jobs are going to be a simple return to whatever dealer is nearest. The contractor who collects your car has nothing to do with the courtesy replacement. Actually, that's not quite accurate; the courtesy replacement procedure often doesn't start until your car is removed!
Don't expect a single recovery of more than a couple of hundred miles. There are excellent reasons, both for you and the workers, why this is the case.
I've been an AA customer(and member before the sell-off) since I was 18, and have never had bad service apart from their renewal policy. If I was going to choose another provider it would be National Breakdown, but that's based on experiences from several years ago.