Which BM autos are better/worse - GM or ZF?

[pundit]

I've read many times about the poor reliability of ZF4HP22 autos.
However that seems to be more of an issue with the earlier (pre '87) ZF's commonly failing due to the 'A' clutch problem. Though it does happen with the later trans it seem less frequent. Bear in mind that most of our 'vintage' bimmers are hitting the 15 year+ mark with maybe 200,000 mls or more on the clock.
However I seem to see at least as many posts concerning failing GM autos. Is this most likely simply due to the mileages now being clocked up or do the GM's have their own failings?
My ZF4HP22 currently has 175,000kms on it. (About 110,000 miles)
From experience I would expect an auto trans to survive at least 300,000+ kms (200,000 miles) before needing a rebuild. Of course if mine fails before this I will be peeved but, would a GM last any longer?... AND bear in mind a GM is quite a bit more expensive to rebuild. So is a GM equipped E34/E32 really any better on the hip pocket maintenance wise than a ZF4HP22. I somehow doubt it from what I've read here.