Anyone ever down convert 2.5 to 2.2 in 00 outback?

[Radial GT1]

The 2.5 engines seem to be crap, or at least this one that is in the car. This is a friend's car, she is in college and strapped for cash. It is a 00 outback with the 2.5. I have done the head gasket once on it and had the heads resurfaced when I did it, and they let go again. The fact that she drove it 20 miles overheating before I did the gaskets didn't help any either though.

I guess my question is, is it worth trying another 2.5, or is it easier to install a very well designed 2.2 engine?

Also, anyone have a 2.5 engine with decent low miles lying around they'd like to sell?

Thanks