BRC HP-500 High Gain 460-470 Mhz GMRS Band Repeater Base Antenna-11.7dB Gain

Wondering if anyone has tried this base station antenna on their GMRS setup ? , lots of gain for the price , would like some feedback on its performance .
BRC HP-500 High Gain 460-470 Mhz GMRS Band Repeater Base Antenna-11.7dB Gain
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They’ve been about for a long time now. The majority are 3 5/8th stacked and have around 8-9dBd gain, which is pretty useful, and a low angle of radiation, great for repeaters. The critical downside is the joints. They’re plated and when first assembled you need to make sure they are done up really tight. Tight enough you can’t get them apart, then you need to water seal them. Heat shrink and self-amalgamating tape at the least. I’ve heard one person advocating epoxy. The problem is the machining is quick and dirty, so when they are tight, sometimes, at that point in the rotation the faces are not parallel so the water can get in, corrode where it settles on surfaces where the screwing in has exposed the real metal and after a few months, your performance degrades.

They’re also quite heavy and being tall, they need a really solid mast. Normal thin wall tube bends and fractures with the constant flexing, so for anything other than short, it means 2” support tube.

The flexing also means really good fixings.

If I really needed the gain, I’d happily use one.