I also have the Comet CA-2x4SR antenna with the SO-239 mount and will agree it works quite well. I have had it for over 10 years and it has never failed me yet. I really like the fact it is quite broad banded. It easily works the provincial Emergency Measures Organisation's SAR repeaters with their 143/149 MHz split.
Hey what kind of SO239 mount do you have? I'm looking for a roof mount type.