The OP mentioned a Tram 2486-B. I'm unable to find that model. Maybe the OP meant Tram 1486.
The only thing that would sell me on a Tram, is the fact that they’re not hollow tubes like the Comet.
What makes you think that the Tram isn't a hollow fiberglass tube with a stiff wire running through it? That's the way almost all vertical VHF/UHF antennas with fiberglass radomes are made. Cut any of them apart and that's what you'll find.
The issue with some antennas of this design is that they are made as multiple sections that have to be assembled in the field. This is done for shipping purposes. A "real" antenna of this design, such as a Phelps-Dodge Stationmaster, now known as the Commander Technologies series, is shipped as one piece. A Commander Technologies 455-7N, which covers 460-470 MHz with 12.1 dBi of gain and is priced at around $2,000, is 19.5 feet long and is shipped in a 24-foot long tube. By comparison, a Comet CA-712-EFC has 9 dBi of gain, is 10 feet 5 inches long, and is shipped as two pieces. If the joint between the two pieces isn't properly assembled or if it fails, then the radome leaks. Of course, the Comet is an order of magnitude less expensive.