It depends. Stitch has strength as well as climbing abilities, while Jim has his solar surfer. Also, Jim has a little more brain (not saying Stitch isn't smart) and if he could get Stitch near some water..

Although if Jim used his solar surfer, that would be running, not fighting. And Stitch can hold plasma blasts in his hands- so Jim's gun would be useless. Stitch would easily overcome him with his strentgh.

..Why does nobody ever really comment on these?

I agree, it would be nice to hear more people explain their choices, whether they're making this about logic or polularity, as Scar beating Sorceror Jafar is outright ludicrous.