The reason why M5 calipers are more prone to seizing is that you have four times the pistons in the front. Statistics says that the more pistons you have the more likely one is to sieze. Even single piston calipers sieze with regularity on older BMWs. Where you get your pricing I don't know, but I personally would never purchase a NEW caliper from BMW. I would purchase a rebuilt unit. OH AND AS FOR M5 FRONT CALIPERS HAVING CARRIERS, THEY DON'T!!! And I hate to tell you, you actually put on brakes that disperse heat worse than the calipers and brakes you took off. Also you will notice, that the pad area is the same, and the M5 rotor is actually thicker than the 750i. And the 750i rotor if diameter is important to you, fits under the M5 calipers. So please please don't replace your M5 calipers with "upgraded" 750i brakes. You are not adding braking. Trust ME! I know about this because I have done the braking tests.

Rob A.
M535i SIG Chief Technical Advisor
www.m535i.org

I had the same problem with 2 1988 M5s which I have owned in the past and couldn't understand the reason why this happens. I called the "dealership" and got a price on getting NEW callipers. They are $ 582.00 each NOT including the carriers. I figured out that to get the parts from the dealership was going to run about $1,700 (for parts only). There had to be a more cost effective sollution to my problem. Im not cheap ( I can't afford to be, I own 2 M5s ), but I want to find the best, most cost effective way to fix my car and improve it at the same time. So I came across a gentleman on this board named STEVE HAYGOOD.HE can get you almost anything you need or could want for your BMW. I bought 2 sets of "pre-owned" 750 front callipers and carriers along with BRAND NEW GERMAN rotors and choice of NEW PADS for around $325.00 (each set). I am not affiliated with STEVE or his shop in any way, I'm an M5 owner who has had terrific service with Steve over the past 3 months, and wanted to share this information. Shipping is extra and the items will be sent from his location in GEORGIA ( ATLANTA not RUSSIA ).
GOOD LUCK and SAVE a TON,
JFK

I never stated that the 750 calipers were "better" I mentioned that they were a "cost effective solution" for almost everyone who has an M5 with front brake seizure problems.I couldn't find ANYONE who would rebuild my calipers for half of what I could buy the whole other set-up for, So that is why I chose the 750 calipers. They just bolt right in. Four pistons are better than one, but one is better than three.
Sorry to those of you who couldn't understand what I was referring to.
Thanks,
JFK