Actually, in some aspects, I would say that Chichester was better than Edinburgh...
First, the theatre and the stage. It is a small venue and the stage is "inside" the audience, so you are so close that it's an experience you can't live in Edinburgh, as it's a normal theatre where everyone is in front of the stage. Here, the actors are with you in a way.
Secondly, the beach, having a beach as part of the stage creates a sense that the Edinburgh show didn't have. I honestly hope that if this goes to London, they do the same.
Third, the actors who played the main roles were as good than Edinburgh, in fact in some cases, for me they were even better. Gabriel Ebbert was far better as Mac than was Damian Humbley, who had a great powerful voice, but Ebbert actoral skills are from out of this world, no wonder why he has a Tony award from Broadway. Also Paul Higgings was a better Gordon than Matthew Pidgeon in the sense Paul provided the character with a more humanized feel, he was cold when he had, sentimental when needed, with more soul. Lillie Flynn was as good for Stella as was Katrina Bryan, both provided the role with character, soul and power. The rest of cast in my opinion were Ok, but Edinburgh cast was a bit better for me.
Fourth, the music. I think it was also better than in Edinburgh. The musicians were playing reading sheets in both Edinburgh and Chichester, so it's clear all music was rewritten as apart of the three new songs, the rest also have different arrangements, sometimes slightly but noticiable. All those changes were for better in my opinion, specially when it comes to the guitar parts, now there are more MK guitar licks that makes it more enjoyable. Also the first number is far better in Chichester, with a lot of effects, even fire flames! Also Gabriel Ebbert sung "Houston, we have a problem" literally "suspended in the air", which was so effective to create the sense he was in a plane flying... I guess it wasn't that nice for him, LOL
The only thing I found not as good was the second half, where some songs from Edinburgh dissapeared and were substituted by some other songs reprises, and also there were a lot of talking during the second half, which for a musical is weird, but considering how brilliant the first half was and that most of the musical reprises of the second half had a lot of MK guitar things here and there even the smallest of the them were worth.
It this goes to London, which I hope it does, I hope it is more similar to Chichester than to Edinburgh in general, and I trully hope they can have Gabriel Ebbert and Paul Higgins, with Katrina Bryan, and also Adam Pearce as Viktor, he was far better in Edinburgh than the one in Chichester. Also I hope that in musical terms, the London one would be similar to Chichester, also I hope they can arrange new songs for the second half.
Also I hope that if it goes to London, it goes with a cd release, that I wish contain the music played by MK and his musicians at British Grove, with the voices from the cast, it is meant to be in these cases, also hope for a bonus cd with some of those songs sung by MK, but that looks unlikely once you see them at the musical.