Decided to go with AAA-SoCal, getting their regular coverage with RV+. Costs $104, and gets you towed 100 miles and some other perks, and covers your motorcycle and trailer too.
If you're interested, contact Rob Sara of their Tustin office at
Sara.Rob@aaa-calif.com, or 714-734-4476. He knows RV stuff (my friend with the blown tranny in Mammoth gave me his number; he got it from rv.net). He was super helpful (NorCal AAA still hasn't returned my calls or answered my emails).
Now here's the dealio with the different AAAs: if you are a member in AAA NorCal, they do the dispatching. Which means probably more wait if you're getting towed in SoCal. Since I'm a SoCal member now, that means it may take longer to get my van towed in NorCal. I can still get many of the services of SoCal here in NorCal, but it sorta depends on the office.
But he also explained that I could retain my NorCal membership (although they have annoyed me enough that I may not). That might make it easier to get some local services, and perhaps a faster battery change or whatever on my other vehicles. Dunno if it's worth it, but now that I get the RV+ coverage I can drop my separate motorcycle towing coverage and the amount I'm paying is significantly less in total than my previous Premier membership.
I asked about the clause I'd quoted above; he says that they have moved beyond that in the last two years and that they essentially get you the tow rather than passing it off and doing reimbursement.
Also, the AAA towing benefit is for you, not the vehicle. So if I'm riding in one of your vans, and you don't have ERS, I can call AAA and get us towed. Note that with some other providers the service is tied to the vehicle.
Whew. This was more trouble than breaking down, but I did learn a lot.