If it's within your travel distance, BTS is highly recommended.
It is similar in that it is a retail dive show that is one of the top few- I travel to various of them over the years.
Each show draws different crowds, in Chicago the audience is either Warm Water Pretty Fishes or Lake Michigan technical guys.
Out East, they have access to a much larger array of wrecks that are in better shape, and remember that all show booths throughout the US are populated by destinations that are easily accessed by that specific gateway city.
At BTS you'll see any number of resorts from Bermuda down to St. Barts that we don't easily travel to from Chicago. At OWU, the Belize resorts are better represented. It's geography.
You'll hardly notice the difference. I think OWU had a better selection of speakers in some regards, quite a few from The History Channel and Deep sea Detectives. BTS has JJ and Sylvia Earle- no slouches either.
They are both first rate shows, much more interesting than any DEMA offering- but DEMA is not meant to be what this is.