I picked the car up from the installer today. The odometer read 106130. My first trip consisted of about 30 miles of mixed driving, both around-town and interstate. Here are my initial impressions of the tires:
Fit: These tires are only one size larger than stock on both front and rear, so they aren't that much bigger. They do fill out the fender wells a little bit more than the oem tires, which I like. Both front and rear fit fine, and cause no problems with the TCS. I had read an assertion before that size P22545WR16 is too large in the front and would rub, so I tried a few full-lock turns to test it. I can report with confidence that the fronts did not rub and are not too large.
Handling: The car handled well and predictably up to 75mph on the interstate and around town, with no TCS problems or other issues. I did detect a bit of tread "squirm", which seems normal. I usually notice a little tread squirm on any new set of tires I have owned. The new, taller tread flexes more than a tire with less tread and some wear. Nothing unusual.
Ride Comfort: The tires seem to provide a much more comfortable, less harsh ride than the tires they replaced. Maybe it is deceiving because they are quieter, or because the thick new tread provides a bit more cushion, but the ride seemed a lot smoother.
Noise: MUCH quieter than the FM901s on the rear. I am glad to have that whine gone, although as I recall the FM901s were also quiet when they were new. They only started whining after several thousand miles. The Nexens seem equal in quietness to the MXX3s, which have a very conventional tread pattern and are nice and quiet.
Appearance: Handsome sidewalls, not quite as sexy as the FM901s, but somewhat more attractive than the Michelin Pilot SX MXX3s, which are great tires but kind of plain jane in the looks department. The tread design isn't my favorite look but it is acceptable. This tread design seems to be the "latest thing" in tire engineering and supposedly sheds water well, so I will defer to wet-weather performance over looks.
Cost: I ended up ordering the tires from two different sources to get the sizes I wanted. The rears were purchased from Ebay Seller "Tiresfast" and cost $184 delivered, shipping took five business days. The fronts were purchased from eastcoasttires.com in Asheboro, NC and cost $139.41 delivered, shipping took three business days. Installation cost $114.25, for a total cost of $437.66. Note: I could have purchased the rear tires from eastcoasttires.com for a little less than through the Ebay seller, and they would have all been delivered at the same time. I only discovered eastcoasttires.com after I had already ordered the rears, but either seller is a good source, for these tires and others.
I will pick up this thread later to discuss how well the tires actually perform.
On a side note, the installer deflated and collapsed the inflatable spare and replaced it under the hood, but I had to put the bolt back in which holds it down. While I was doing this, I noticed that the spare tire had a crack running around one edge, apparently due to age and dry rot. I will need to replace it. Maybe others should have a close look at their spare tire also? I am also in the process of replacing the air pump, as the one I have (not the original but an aftermarket pump) has a universal-type connector which wouldn't inflate the spare when I tried it. After doing some research, I learned the BMW M5 doesn't have a spare tire at all, and comes with an air pump instead. When I had a look at the BMW pump I saw that it doesn't have a universal-type connector, but an actual screw-on connector, so I intend to acquire a BMW pump as a replacement.