as described in detail in the UK price list catalog (which also applies to US cars)...
extended leather: the seats, headrests, rear storage pocket, door panel middle insert, arm rest & lid, lower center instrument panel, handbrake boot and SMG gear shift boot in Merino leather while high-wear parts like the actual handbrake and gear knob are in Nappa leather.
full leather has all of the above but adds: upper & lower door panels, lower instrument panel, glovebox lid, and the center console in Merino leather while the dash and upper instrument panel are in Nappa leather... and finally, the headliner, sunvisors, rear parcel shelf, A, B, C pillars are in Alcantara.
Almost sounds like it's not worth the extra $3500 doesn't it? I couldn't resist the alcantara and the indy red interior so I had to bite.
Thanks for your reply. That is very helpful. I just recently started thinking seriously about the M5 and my local dealers are asking $20K to $25K over MSRP which I will not go for. Yesterday a broker called and said he can get me a car in 3 to 6 months for $1K over MSRP so I started to look at the options closely. I do want to get a M5 but can't decide if I want to wait for a manual tranny. I am also trying to decide if I will keep or sell my 2003 Porsche 911 Turbo X-50 if I get a M5 with the manual.
I chose the Extended Leather. $3500. is a lot of chiing for a headliner and some dash and door pieces. As for paying over MSRP. There are plenty of dealers in smaller town in CA that will sell at MSRP. Go on the BMW NA website and you can find every dealer in the country.