Aerocity worked for me, too, though I wish they'd get their phone act together--I spent a helluva lot of time on hold from pay phones. Otherwise okay.
I'd reserved online, but my flight was delayed 8 hours (!), so I called when I finally made it to the airport. I was transferred and put on hold a few times, but in the end they said there was a driver at the pickup spot and since they told me what color and type of vehicle to look for, he was easy to find (unmarked van). So I had no wait, and wound up being the only passenger. I'd wanted to arrange a pickup from a bus station to the airport for the return home, but after putting me on hold about 5 times, the representative wouldn't accept my reservation in case the bus was late (something I've yet to experience in Spain, BTW). When I arrived at the station, I didn't feel like waiting but I didn't have a good feeling about the first cabbie on line, either. So I asked him approximately how much to the airport, and he estimated 4,000. I went inside and called Aerocity instead. Once again, I was put on hold several times and had to keep feeding the phone. But they did send a driver in 20 minutes, I was the only passenger, and with the money I saved, I bought a very nice bottle of wine at the airport.