A/C boat show (the one at the convention center, not the in-water one, I've never been to that one so can't give an opinion on it) usually has a very good variety of electronic dealers/manufacturers displaying their equipment. There, you can check out various displays from the top named manufacturers. You will also get a discount on the price if you buy at the show. But be sure to shop priced as they will vary widely from booth to booth.
My opinion is, most of the major brands offer fairly similar products. Therefore, it will be a personal choice as to which is the best machine/manufacturer.