I had to replace mine yesterday (front right) and as it turns out, Autozone had the Dorman Part in stock locally. it was $123 but I HAD to get it done. Unlike some, I've actually had pretty good luck with Dorman in certain instances and other than suspension, i am not afraid to selectively experiment with (the HORROR!) a non OE part. I put in a Duralast alternator a few weeks ago and that was a bust. It made a terrible whistling noise in the electrical system. But it was an emergency again. Didn't have the choice. I was able to put the old one back in with a new regulator and was good to go. Plus, I can change that alternator in less than an hour now, lol!
A few notes:
1. I have done no fewer than 8 of these regulators over the years.
2. With the age of these cars, just about every time I remove a door panel now one of the brackets rips from cardboard. This didn't happen 6-7 years ago. Yesterday, the entire top plastic frame came off the inside of the card. I'm sure you can use just about any kind of glue, but i have had very good luck with the JB Weld Plastic bonder reattaching door panel brackets (that hold the little gray and white pegs). I'd suggest sanding the previous mounting surfaces with 80 or 100 Grit. Plenty of time to position everything it's good to go within the hour.
JBWELD
3. I've had regs fail at the clips only, the sliders, and the cables. Separately and together.
4. ODDLY, the door vapor barrier on my 2005 Xer is SIGNIFICANTLY stronger than that of my 2003 Xer, which ripped like tissue paper no matter how gingerly treated.
5. Be careful not to lose your Airbag plastic cover label thing. They are EXPENSIVE ($60 plus at FCP) to replace and there's a hole in the door panel if it's not there. Also, be careful removing it so you don't break the plastic. BTW, i NEVER remove the airbag and have been known to uhhhh...just let it hang for a sec. I know i know!
6. I keep a couple of small suction cups with my tools because they work great to hold up the window while working on the regulator.
7. I've used regulators with new motors before. I'd suggest buying the one without the motors and use your Bosch motor. It will keep the roll-up speed similar. And...real German.
8. Don't overtighten the 8mm bolt holding the window.
9. ALWAYS keep a bunch of door card pegs (white and/or gray) and 2 spare regulator clips in your BMW parts pile.
10. use a single edge razor to cut the tar strings. when pulling away the vapor barrier. makes it MUCH easier.
11. put a little bit of the vapor barrier tar on the inside of your 8mm and 10mm sockets when you are reinstalling. Stick the nuts in there prior to threading and they won't fall down in the door cavity when you are reinstalling. I
actually keep a small sheet of Dynamat with my sockets for this and use it all the time to avoid crap falling onto the stiffening plate!
12. be very careful removing the wood trim piece and don't break the ridiculously delicate bracket where it clips to the door handle. REMOVING: lift up on the far end. REINSTALLING: place the bracket first and then work your way toward the door lock when pushing into the mount holes.
13. I bought the regulatorfix brackets one time and they sent me the wrong ones. but that looks like a good solution potentially. Keep regfix brackets and clips handy and if the cables don't get jacked up (only happened to me once) you're good to go repairing most reg problems.
14. if i think of a few more tips i will post them!