Well, nobody is answering this so I'll give it a shot:
The 22r is an 8 valve engine, the 2RZFE (or 3RZFE) are 16 valve engines.
They are both rock solid, but you have to consider the complexity which is a trade-off in power and efficiency.
I think the 2RZFE is every bit as reliable as the 22R but give up something in complexity, if that makes sense.
To get the increased power and efficiency, you have to give up something, so if I had to pick an engine for extreme circumstances, maybe the 22R because it is simpler to repair and rock solid.
For day-to-day, though, give me the 2RZFE, because it has the power and efficiency that were lacking in the 22R. Yeah, have to adjust more valves, have the shim and buckets, don't know what else someone will point out that is different, but just give her her maintenance and she'll run fine and reward you in daily driving.
My $0.02. Chipsndukes