Here's what Dave Johnson, Chief Engineer had to say about the BH
The BH Tracker 4 doesn't have a lot of performance or features, but within its limitations it does what it does very well. Predictable and easy to use. The approx. 6.5 kHz operating frequency, and low sensitivity compared to an expensive machine, allow it to be used on a saltwater beach with little difficulty although if you're where you're actually getting your feet wet you'll probably have to reduce the sensitivity and/or increase the discrimination level. ......Although as an engineer I'm constantly looking at ways it could be "improved", the boss reminds me that of those people who actually own a Tracker 4, it's almost impossible to find someone who's unhappy with it, so "if it ain't broke, don't fix it". A surprising number of people here in the USA who have expensive machines have a Tracker 4 as a backup or loaner machine. .....I used to know a guy who'd had several expensive machines and never liked them, and gave up on metal detecting, but then oddly his wife gave him a Tracker 4 for Christmas, and he went out to the park and learned out to use it, and from then on out he spent many hours a week "cleaning out" parks in Colorado, often embarrassing the heck out of other detectorists who had shown up with expensive machines that they hadn't learned how to use properly for coinshooting in a public park.
However, for those who favor, he simpler, meterless Compadre, Dave also said this.
Nowadays there are machines with visual target ID down to about US$100, in the same range as low-cost machines without visual target ID. In this price range, machines without visual target ID generally provide a more nuanced audio response and more control over discrimination. That's the tradeoff. Given that choice, my personal preference is the units without the visual ID. Outside the USA visual ID isn't all that useful anyhow because it is only the peculiarities of USA coinage that make it such a desirable feature here. (Most more expensive machines offer a visual ID system and audio system which work somewhat independently so you don't have the tradeoff that exists with the low-cost models.)