I'm against seeing non-IMAX films in IMAX, because the two times I did so, the film was cropped to fit in the IMAX frame. (One was Attack of the Clones, the other was Apollo 13.) Since then, I haven't seen any non-IMAX film in an IMAX theater.

The cropping of the Star Wars movies to 70mm is the difference between 2.39:1 and 2.2:1, which isn't that noticeable.

I'd much prefer a preservation of Star Wars to be from the o-neg, or the first IP struck from said o-neg. If neither of those can be used for whatever reason, then a 70mm print would be next in line.