I don't have one so can't say how that Comet would stack up against the Wouxun supplied antenna. I can say that Wouxun has made a change in the 'duck' antenna supplied with the new model 'UV6D' HT, and it is an improvement over the older supplied antennas. That opinion is from experience, not just what I've heard. The new 'duck' on the 'UV6D' is something like 1/2" longer and is constructed differently. I've used both the old/new ones and while the difference in performance isn't huge, there definitely is some improvement.
I don't have any 'scientific' figures about the difference in performance, it's only from sitting on my front porch and seeing what I can 'hit'. The local repeater is about 6 miles from my house, and was marginal with the old 'duck'. With the new one, it's a solid deal. Same output power so that's not a factor (used a 'UV2' and then a 'UV6', and swapped the antennas).
The improved performance is relative, keep that in mind. Neither compare to a typical mobile antenna or base antenna, naturally. I was honestly surprised, didn't expect that sort of difference. If I can find a source for the new Wouxun 'duck' antenna, I do plan to change the older 'duck' out for the new one.
I'm making some changes in things here so 'playing' with the HTs is sort of on the back-burner for now. I do plan to see what the results of trying a few of the 'quick-n-dirty' tricks with 'duck' antennas are, don't hold your breath though.
And the 'disclaimer' (naturally), your milage may vary from mine...
- 'Doc
(FWIW - I just heard from the 'candy store', the Wouxun antenna goes for $15.00. Not sure about shipping.)