Hi Ex Xm,
In perfect honesty the Auto box is a matter of our opionions!! Some have had early failure, others have had a massive milage from them. My Mate has a 2.1 TD Auto Exclusive and the car is now on 188k, the REAL key is VERY regular gear oil changes, probably every 3rd engine oil change..
The thing to look for is find a GOOD auto box that has smooth changes, then give it a fluid change..
Setting the car to low through long periods of inactivity is rubbish - XM's WILL settle down to the floor over time nautraully..!
The Models around 1993 to 1994/5 seem the best bet - Im baised towards the Late Series one cars of these years, firstly, as the syspension is rather faultless, obviously we DO NOT know exactly how much about XM's you know already..
With XM's the key is get one thats Mechanically CORRECT rather then spec, you can ALWAYS add leather and alloys if that tickles you at a later date. With a full set of "Proper XM" spheres the ride is NOT as soft as a CX, but is STILL DAMM GOOD when the electro valves ARE operating corectly, however these are useually a problem on later cars, Late M reg onwards with the revised Dash style, and tiny spoiler (On Hatches) and Air bag..
Having said what Ive said about auto box's, I dont think there a concern for worry, as theres a couple of people about now, I think even a member on here, who can fix auto boxes. I know there is an autobox fixer on
http://www.frenchcarfourm.co.uk
Bosch equpit cars are best to go for - these available from around 1993 to 1997 ish...
Im sure there will be more along to give their opnions .
Place to buy - Mr Savoy Garage, has currently got 2 XM 2.1 TD Autos in, estates too!!
He knows his stuff TOO!!!
Very knowledageble, and what he says is what you get too! Click his Cars for Sale section
Regards
PAul