The unit is well made . 5/8th wave on 2 meters. Should you wish to trim it shorter for better SWR they send you a chart so the guess work is not hard. I found it great because I'm using it for FM repeater communications and it came perfect for that so I didn't need to trim to get better SWR. For me the coax was decent and perfectly long enough. The magnet mount itself seems good for normal driving speeds. It has a cover so it doesn't scratch my paint. Easy to remove as my area has parking garages which was my main concern . Secondary was so I wouldn't get targeted for break ins which happen frequently in the garages I must use to park for work. Plus to change autos with the antenna is very easy to do as it's not permanent and I use a radio with a cigarette lighter power source so the portability factor is very nice . All in all a very good unit and would recommend it as a low cost great value unit .
I needed a mag mount so I could move the antenna between vehicles. I manage communications for a major cycling event in my area and I have always found a 5/8 wave to be one of the best choices for 2 meters. The RUM150 nails it. The base magnet is strong and the cable length is more than adequate for my crew cab truck. The instructions provide a table of length adjustments if wish to tune to a desired center frequency.