Having always had agreed value classic insurance on all my older cars for the last 26 years, UK & EU breakdown cover has been included. I've used it twice and it's been very good.
On my Subaru Forester (too young for a classic policy) I had RAC cover and needed it when the radiator blew last year, 104 miles from home. They were appalling. In total it took 27.5 hours from we broke down (25.5 hours from when they agreed that we needed to be recovered home) until they actually got us home. 8 hours to take us 40 miles and leave us stranded in a lorry park at 9pm, where they had told us another truck would be ready to take us the rest of the way. It wasn't. Over the next 5 hours they repeatedly told us that our situation had been "escalated" to "another team" and to expect a phonecall/a truck/a taxi/etc "within 45 mins".
We gave up at 2am and found a hotel, being promised that a truck would be there at 7am. It finally arrived at 1pm and got us home at 4.30pm.
Then when I complained, I found out that their customer service is even worse than their recovery service.
Before anyone thinks of signing up to the RAC, I suggest you have a quick look at the Facebook group " RAC how bad are they", where you'll find that we were quite lucky with our experience.