Turns out, I had bought the same kind that Felix recommends above
First impressions - smaller than expected. I like the voice confirmations. Decent controls, save for the mute button (might be a matter of getting used to). Micro USB is not a great choice nowadays, but whatever. Sound quality - very good (though only tried it in the back yard). Earpiece/headset seems a bit too …lightweight. Not sure about the fit in the ear and how well they’ll stay there. Additional tips and “prongs” were included. Might have to play with those.
I asked for belt clips (these units come only with arm pouches) and was given a set for free. Not very good ones and the seller was honest about it. You have to leave a couple of bolts loose on them in order to be able to slip it over even the thinnest belt. There’s a different spring included, but it’s also a rather poor fit. Not a big problem, but it takes away from the otherwise neat units. Perhaps a different set of clips would work better.
@Felix, what do you use?
Also the manual mentioned firmware update, but it’s not clear where to get it from.