Going with Hime No Toki on this - yes, judges will flip over your seams as you are wearing it. Tastefully of course, no looking up skirts I promise.
I've not judged a competition where you weren't required to be in costume at the time of judging, as usually general presentation is considered as part of the whole. You can't judge how it all fits together (wig, makeup, overall fit, overall impression) on a hanger.
No judge is going to give you criticism in the judging room, and if they do, that's extremely unprofessional.