I am the owner of the Azurite black M3 that you quoted. After two years of ownership, I can safely say, I would do it again (over Jerez), in a heartbeat!!
With any black car, one must be careful. I am (VERY), and reap the benefits - i.e. - very, very few swirls (that said, I give the car a very thorough (read: two-day, 26-hour+) full detail every year, and do swirl-mark touch-ups as needed.
To those that say Azurite is too close to Jerez - I would tend to think they have not compared them side-by-side. Azurite GLOWS - it has a very pronounced depth, and the number of people that have asked if I had it custom painted is innumerable!
When deciding on the colour for my M3, I only had a couple of (fairly scratched up) colour panels, about 6" x 4". I compared Jerez to Azurite, and to me, they looked pretty close (the metal flake was finer on the Jerez panel). However, when I compared a Jerez CAR with mine, the difference was patently obvious.
Regarding matching the paint - do NOT worry - I had an unfortunate incident with a fallen deer recently, and had to replace the front bumper. I chose my body shop carefully, and it paint work is perfect. I am (almost) as anal retentive about my paint as Jamie (BMWLVR), LOL, and cannot tolerate even the slightest imperfection. Those that say you won't be able to match the colour have no clue.
Too bad you weren't closer to me - I'd be VERY happy to show you Azurite in person!
Oh - and, this might be as telling a tale as any - I have met three other Jerez owners, who, after comparing their cars to mine, ALL wished they had stumped up the extra $$$ to go with Azurite....
Good luck with your choice!