Just to add some perspective - I also had my tranny fail on my 92 500sel. It started skipping second at 145k miles, then stopped finding fourth at 158k, and then started finding false neutrals at 160k, which was the end of trying to live with it.

I was quoted about $4500 from the dealer, $2500 from a good indie shop, $1800 from a large trans only rebuilder, and $1300 from a small shop that does Mercedes trannys only.

While I too had to wait for a valve body swap to make it perfect, overall I'm pretty happy. It shifts a little bit more aggressive than it probably "should" (running to higher rpms before shifting, firm positive shifts), but I drive aggressively so it works for me.

If I had to do it again, I would seriously consider the $1800 deal - primary reason being that they have a tranny dyno, so the trans can be fully test run after rebuild, but PRIOR to re-installing into car (which I think would avoid some possible problems). (They also offered a very thorough warranty (including towing, etc.), although the dealer did offer the best warranty (at a cost of only $2000+ (for the warranty))

-David