This is where reading the fine print is important. GSRA and Coachnet both provide towing TO THE NEAREST REPAIR SHOP THAT AGREES TO TAKE THE VEHICLE. They pull up your location and start calling the nearest shops on their list until one agrees to take your vehicle.
This works great if you don't have a preferred shop in the area, don't have a warranty, and it's not a holiday weekend.
If you have a preferred shop - you can only be towed there if they get the service call and agree to take your vehicle.
If you have a warranty - you can only be towed to the warranty approved shop if they get the service call and agree to take your vehicle.
If it's a holiday weekend - the RA service will have an even more difficult time reaching a shop (most are closed and not answering the phone) and getting them to agree to take your vehicle.
If you need to be able to take your vehicle to a specific shop, then you should get a service that doesn't locate the repair shop for you. For example, AAA will tow you anywhere you want - they have a limit of how many miles worth of towing you get for free, but if you're willing to pay to go further, they will tow you there.
For me, both types have their benefits and both have their negatives. Having both and using the best one for each specific situation is the easiest way to success.