I appreciate every body's opinions, so don't think they're being ignored.
The reason for the antifreeze flush is because the engine is aluminum, and I've read a great deal, and talked to a lot of mechanics about the damage that can be caused by neglect.
(Google: antifreeze PH balance.) It's good to know that the antifreeze that comes in the car is something "special", and I'm going to specifically tell them that's what I want to be put back in it. My car was built in Jan. of 04 so it's almost 4 years old, so I'm only changing it a year early.

Since my car is an 04 I have always experienced the "notchy" 1st. to 2nd. gear change problem that goes away after it warms up. But until it does, it feels like the syncros aren't doing their job as well as they should. So I have no doubts that there are metal shavings in the oil.

Changing the differential grease may be overkill, but I figured it won't hurt. Besides, my car is a 6 speed and there is more back and forth motion or "play" of the pinion gear than with an automatic. So when there is "movement", there's wear and tear.

Like Idaho mentioned, I too am not a great believer in having the rotors turned down, and I've been giving it a lot of thought. I think I'm going to just have them replace the pads and that's all.

As for oil changes, I do them myself. I did go over 5k once, and that was the first time I ever heard what sounded like "lifter" noise. Up until that time my engine was as silent as a church mouse. That's why I change my oil and filter between 4 and 4.5k. I use nothing but Mobil 1, and a Mercedes filter.

I'll probably change the air filters myself next spring.

I knew the spark plug 15k mile "factory suggested" change was bogus. I just wondered if anybody else had got the same news from their dealers. I still haven't priced them out, but $300.00 seems outrageous.

If I didn't plan on keeping this car for a very, very long time, I probably wouldn't do half of the things I've been doing. But until I can find a good Mercedes mechanic that is willing to work on my car, I'm going to try and do as much as I can to prevent the need for unnecessary repairs.

I'll let everybody know how well the dealer did, and how badly or how well they treated my car. I am going to put tape over my door sills (where everybody likes to scuff their shoes) and I wish I had a steering wheel "cozy" to protect my cedar wheel from dirty hands, but I don't.
It's going in Wednesday, so stay tuned.

Thanks everyone for your input.