They work. I personally wouldn’t want to use one all the time. I’ve had one it did work but I spiked it first chance I got . A plastic bic type pen cap, a small fine threaded bolt will work in a pinch as well. Best of luck

I too have one, mainly because I had a spike fall out & wanted something to tide me over until I could get the builder to fix it. It worked fine, more of a hassle to switch back & forth than a spike. I fear I will loose it sometime as there isn't a place on the banjo to store it. Well made & such.

My banjo is spiked up to the 10th fret but I bought a strum hollow capo for the rare times I want to play in D with the 5th string capoed at the 12th fret. It works fine. Storage is not a problem, I just attach it to the 3rd string an inch below the tuner when I'm not using it. It also can serve as an emergency backup for a spike coming out or breaking although I've never had that happen with the spikes I've placed myself.

I've jammed a bit with it (actually the original "Reagan" capo, but exact same thing), using it on one neck I either didn't have to spike before a festival and another I just didn't get around to spiking for many months. Bought mine in

Verdict: Yes, it really works. But I find it inconvenient.

It doesn't always go easily onto the string, so I find myself fussing with it. If you don't sufficiently back off the set-screw, the capo doesn't go onto the string far enough and can come off while you're playing even though you've tightened the screw. The base of the capo is taller than the frets, so the capoed fifth string stands taller than it would if spiked or held down by a sliding capo. And on mine, the felt on the bottom started coming off right away. It'snow just a wisp of its former self.

For me, it's a short-term or emergency solution either for an un-spiked neck or in case a spike comes loose during a jam or gig. I store the capo in my pick pouch. At a jam, it's in my shirt pocket (if I have one). Bought mine in 2015.

I bought one for an old open back Vega that I didn't want to spike.

As said above, it does work if you get used to opening the set screw far enough to go on the string and if you can hold it steady enough when you tighten the set screw. I often found it required two hands.

Finally, it is EASY to lose, especially if working on stage!

The original Reagan had a brass set screw, the newer Strum Hollow uses a white plastic set screw. It makes the weight a little different, but they both work the same.

Thanks for all of your replies. Looks like I am going to order some spikes.