I posted this response to a similar question on the AMSAT-BB mailing list not too long ago:
At the time we had SO-67, AO-27, AO-51, and SO-50 available, I owned
one of those antennas. I probably made somewhere in the vicinity of
250 contacts with it from my car.
For reception of all those birds, I would rate them as follows:
AO-51 - Worked modestly without preamp, excellent with preamp, even in motion
SO-67 - Almost as good as AO-51, even in motion
AO-27 - Didn't work very well unless I was completely stationary, even
SO-50 - Barely usable unless I was completely stationary and it was
the *right* pass
I wasn't active on the linear birds at the time but I suspect it would
work a lot better for FO-29 than any of the FM's. I sold it before I
added full duplex SSB to my mobile station.
If you are looking for something mobile/portable, there are much more
cost effective solutions with similar or better performance. I have
experimented with a number of antenna combinations over the past three
If you're dead set on a fixed omni, it is hard to beat a 19" whip
combined with a receive preamplifier. There are pro's/con's to it.
Personally, I almost always use a vertical for mode J uplink mobile
and a 3-element yagi w/preamp for downlink. For mode B, I transmit
into a dual-band vertical on the trunk lid and listen on a 2m Arrow or
simply use the whole Arrow out of the window. (it can be done, albeit
Please tell us the application for which you are looking into using
the antenna...Mobile in motion? Fixed portable ops from car?