Hello,
I've used both the Maldol AH-209 and the Comet CH-32 "Miracle Baby" on my BC246T. The Maldol is just a little taller but is very flexible, the Comet is solid. I find that 800 is a little better on the Comet but VHF and UHF are better on the Maldol.
If you're just listening locally or trying to use Close Call, these are nice because you're not going to receive strong signals from anything out of the local area. For example, if you're in Disneyland monitoring their trunked system only, you'll be fine with either one. Likewise, if you're in downtown San Francisco and only want to monitor SF, either antenna is fine.
But if you want to listen to more distant users, I'd recommend the Radio Shack 800 Mhz antenna. During my commute into SF, that's the antenna that I attach to my BC246T so that I can listen to CHP as well as SF and news frequencies in the 450 Mhz range.