Have both and they are very similar in a general sense. Both are fast, not a ton to shoot for, sold on theme, and have beginner, intermediate, and advance strategies.
I would ask yourself what you like better for each category and go from there.
Theme > SW wins for me
Shot layout > tied; both are fun to shoot. SW is uber fast but not much else. IM is just slightly slower but way more ball interaction
Toys > IM obviously wins with multiple magnets and monger
Code > SW is WAY too early to tell but it will feel like GoT for sure so if you liek that atyle of play then it wins. I think IM is probably the more well put together package and thus far Dwight has been un able to polish either GB or GoT so I give the edge to IM just because it is polished
Art > I think I would take IM again. SW art is a let down compared to what they could have done.
Aside from theme, I think IM wins for me personally. That may change in 6-12 months IF starwars code gets refined and polished. Reality is that even with both to compare in person it is way to early to make a good decision about any vs including SW.