This is a portion of the reply I posted in reply to Matt's thread on another forum:
"My experience with the J&M CB in-fairing powered antenna has been much different than the OP. On today's HOG chapter ride on I-20 from Atlanta to just east of B'ham (destination was Barber Vintage Motorsports Museum) and there were times when I was leading and the sweep on an Ultra were separated by 1/2 mile or so and never had a bit of trouble talking or listening to him.
I've had the antenna in the bike for all of this riding season which began on January 1st with a lengthy New Year's Day ride and rides with 30+ bikes through rural, hilly areas (either leading or sweeping) and the CB/antenna has worked fine.
I don't know if the OP received a faulty unit or not. But I've read threads from probably a 1/2 dozen other users of this antenna who were pleased with it and had far greater transmit and receive function than what he described."
This is the reply to the thead from the owner of J&M:
"ReefRider ,,,,
I wrote that verbage on the J&M website describing the performance of the J&M in-fairing CB antenna ,,,,
I was personally involved in the initial design and testing of this antenna,,,,
using my own 2010 Harley Ultra LTD, & my 2010 Harley RoadGlide (with JMCB-2003) I found a 20-30% reduction in CB TX distance using the J&M in-fairing CB antenna, compared to the J&M or Harley rear mounted antennas ,,,,,
on one particular day of testing, the rear antennas would TX to the receive vehicle approx. 1.5 miles, and 1.2 miles with the J&M in-fairing CB antennas ,,,,
I also found it very important to route the in-fairing antenna stinger wire exactly as per the instructions included with the antennas, as various other routings inside the fairing would significantly affect performance ,,,,,
in summary, even with the increased solar storm activity that will take place during the next 2-4 years, the Harley or J&M CB radios, on the Harley dressers, with the J&M in-fairing CB antennas, should be able to transmit and receive to distances between .5 and 1.5 miles depending upon the atmospheric conditions on a particular day, time of day or location, urban or rural ,,,,
JMJOHN ,,, John@Jmcorp.com ,,,,,"