I have been running DiaQueen in my tranny for almost 1,000 miles now. It feels the exact same as it did before, perfect. It was around $100 for a gallon and I had to buy it from a local Mitsu. dealer. Rockville said they couldn't ship the stuff.
The trans fluid is of course GL-4. Per
this page the part number is MZ313376 for the trans fluid.