We purchased our second 5er at the show in Illinois. The unit was being shown by the dealer who sold us our first unit. We did not buy our first unit at the show. Looking at your questions - both transactions were the same. I felt we had good bargaining at the show because there seemed to be some sales quotas to achieve.
Yes there were things that needed fixing when we took delivery, but we also successfully negotiated for additional work/improvements with which we were very pleased,
My experiences were very positive and it didn't matter where it happened, but it did matter with who we were dealing.
Good luck in your search.