At the RepeaterBook.com lab, we tested the SWR of the PulseLarsen NMO 2/70 antenna using the RigExpert AA-1000. According to PulseLarsen, the antenna is a mag mount 1/2-wave on 2-meters and collinear on 70-centimeters. The gain is reported as 2.4 dBi on 2-meters and 4.0 dBi on 70-cm. It can handle 100 watts of power with an overall length of 34.5 inches. The equivalent Comet antenna is the SBB-5, which is significantly cheaper.
We tested the antenna on a cookie sheet to replicate a situation such as the use of a go-box at a park. We attempted to adjust the antenna length to the best possible SWR. Your results may vary.
SWR on this band was about 3.4. This antenna is not intended for use on 1.25-m frequencies.
SWR on the GMRS channels ranged from 2.1 to 2.9. This antenna is not intended for use on GRMS frequencies.
SWR on the repeater uplink frequencies ranged from 2.5 to 3.1. This antenna is not intended for use on 33-cm frequencies.
This is definitely a "you get what you pay for" product. The Larsen antenna performed very well on the frequencies most likely to be used by mobile users. It is an antenna that is specifically designed for Ham use on the 2-m/440 bands and it does it very well. This antenna is not suited for venturing outside of the Ham bands or other bands. This antenna is probably one of the most expensive antennas marketed for Hams in this category but performs very well.
This antenna is priced just a bit cheaper than Comet antennas, but the Comet antennas seem to perform a little better for the money.
We will re-run these tests with the antenna mounted to a vehicle and report back on the results.