Yes, was a member of their breakdown service for two years. They use independent garages or contractors for rescue services.
Had to call them out twice - once was ok, fixed an electrical fault by roadside. but I had to wait 1.5 hours before they turned up.
Second time was dreadful. Recovered my vehicle after double flats. Tyres not repairable, so they agreed to recover me home - 130 miles. Sent wrong recovery vehicle first time. Damaged my vehicle while loading it onto the second one. The truck was v. slow, got home at 5 am. Cab was filthy.
ETA ignored my emails and letters regarding complaints and compensation for damage. Always passed the buck on the phone. No response when I didn't renew and told them why - so no points for customer service.
Now with RAC. Much better, not much more expenssive.
Avoid the ETA at all costs.