Cross comparison of inputs on UR models

I have been looking into this question for a while, but as you all know we are constantly trying to solve about 10 problems so having less to solve is of the essence.

I am wondering if the inputs on the UR series are stereo? Meaning, can you feed a stereo signal into the line in jacks with a stereo 1/4" cable? How are the channels mapped. I would like to able able to get the ur22mkII because it is portable (the size and USB 5 V DC in with power source selector which the 242 does not have). But I don’t want to be limited to a 2 channel interface.

Apologies if that sounded stupid or confusing.