I used AV but I learned a lot in the process and probably wouldn't have used them "had I known then what I know now."
First of all: Permits. AV listed something like $115 for the permit and I assume it included their labor to get the permit. I thought that it would be complicated, that the city (Irvine) wouldn't know what I was talking about if I tried to get the permit myself. It turns out that I also got my main panel upgraded and my electrician recommended that I get the permit as an owner-builder. I went to the city office, walked out 20 minutes later with a permit for $48 for the panel upgrade. The same thing would have happened for the EVSE. I would have asked for an owner-builder permit for an electric car charging station. Final inspections went smoothly without either contractor being present, so no big deal about that. BE SURE you are using a licensed electrical contractor if you are going to get an owner-builder permit. Otherwise you have to sign on the application saying that you will be responsible for workers comp, etc.
Second: Connecting the EVSE. AV tried to get us all scared with a bunch of FUD about only their licensed, trained electrician partners being able to install the EVSE. In reality, the included AV manual has pictures and stepwise instructions for the connection. It's three wires, no big deal for any electrician and even for most savvy DIYers. Now, admittedly, when AV's partner electricians install it, they check everything with AV's fancy test box and you wouldn't have that assurance. But if it doesn't work when you plug in your LEAF, send it back and trickle charge until they send you a new one.
Third: Warranty. The way I understand it, if you have AV handle the installation and you have a warranty issue, they'll send a technician out with a new EVSE so you aren't down. If you install it yourself, you have to ship it to them for warranty issues. That's worth something, and it was a consideration when I made my decision.
Running the wiring from your panel: Any electrician can do this. Get several bids from licensed contractors.
My electrician was Jason Wakefield: 714-883-5064.
Jason underbid AV's bid by a few hundred dollars, and he charges extra for his labor to pull permits. Because I didn't know how easy and cheap it would be to get an owner-builder permit and also because of the difference in the warranties, I went with AV. I think I paid about $350 more than I needed to to get that extra warranty. Probably not worth it.
The last I heard, AV charges about $850 including tax and shipping to ship you an EVSE. Be sure to check whether you need the 25 foot cable or the standard 15 foot one. I got the 25 foot, and it will reach my driveway as well as across the garage in case I get a second plug in car.
Holler back or PM me if you have further questions.