There are three 800 MHz antenna types I've seen: Stubby, 3" 1/4 wave whip, 6" 1/2 wave whip.
If the 3" antenna is considered the standard, the stubby antenna is inferior with 3 dB less sensitivity and radiated field strength, and the 1/2 wave antenna is superior with 3 dB more sensitivity and radiated field strength.
In fringe coverage areas, you want the 1/2 wave antenna and do NOT want the stubby antenna.
Tessco is another company that carries antennas for Harris radios.
So is New London Technologies.