I haven't been to many aquariums so I don't have a lot to compare to, but I enjoyed Odysea. We took our daughter here for her 4th Birthday celebration in lieu of a party this year. While it on the pricy side ($102 for a family of 4, one of which was free), everyone had a great time. The volunteer staff was very polite and knowledgable (we only saw them in the lower portion by the octopus).
We went on a Monday (during the school year) so it was pretty empty which was awesome. One of the volunteers said it's not a place you want to be at during the weekend! One thing I wouldn't recommend doing is buy the photos that are taken at the entrance. They are extremely overpriced & not the greatest quality. Again, fun for a bday celebration but I wouldn't do it again.
All-in-all, I would recommend visiting. Unless you buy a yearly membership it's not affordable (for us anyways) to go more than 1 or 2 a year though.