I opted for #3 with my wife's 190e. It has about 160k and it has been leaking from the front seal as long as I have we've had it.

The car doesn't get driven much, so when it sits, it tends to leak more. I'd say its using about an 1/8 quart or less between tanks.

I have a manual trans ready to install, but the auto won't die. I'm in no hurry (to damn busy) to crawl under and R/R, so add I do.

I'd save your money. $900 is about 1/3 of the job. Wait till it dies / wears out.

Tinker

I'm in the same boat.
I hate to see good transmission fluid go to waste, but I think it is a bonus to have a constant slow replacement of the fluid onging.
My leak rate is variable, and I think somewhat weather dependant but I haven't really tracked it that well.
I just check it periodicaly and if it leaks below the dipstick mark I can usually feel it in the shift preformance.

__________________
-Marty

1986 300E 220,000 miles+ transmission impossible
(Now waiting under a bridge in order to become one)

Reading your M103 duty cycle:
http://www.peachparts.com/shopforum/831799-post13.html
http://www.peachparts.com/shopforum/831807-post14.html

Being in the trans business for 15 years,we have found any "stop leak" will swell all seals leading to premature failure!

Just for info!

John1

Do the rebuid, we refuse to "seal any transmission with over 75000 miles. It is a waste of the customers money.

I don't follow the logic here, do the rebuild, because stop-leak will lead to premature failure - premature to what? - obviously not the rebuild. I've had great success with stop-leaks, of all kinds, over many years and not a single problem of any sort. In fact I think if stop-leaks didn't exist I probably wouldn't own Mercedes. They're sort of the backbone of my maintenance strategy.