I've done a fair old bit of holiday mileage (2000 per year maybe, with 600Kg trailer-tent) Belfast to France, through Wales, then via Plymouth, Southhampton, a lot of the South Coast ports down to at least Brest. I've also driven a six-tonner, or a large minibus, all over Britain as part of my Cadet work for 27 years. As far north as Ullapool and as far south as Browndown camp (remember Bad Lads Army?), through the maze of wee excuses for roads in the Highlands, snowdonia and Yorkshire. I've always been spot on with AA.com, even in rural Brittany, or single-track Torridon, but a modern (allegedly up-to-date) sat. nav. has more than once led me astray, until I learned to 'interpret' it with AA.com help. You only have to go to Youtube to see some of the complete bullwarks some ejits have got into slavishly following the disembodied voice beside the tachy....
Sam