Beard Guitars Wave Capo Squareneck

It is pretty and looks great, the problem is that is not very estable, I mean, when you play nothing holds it against the fretboard so it vibrates too much causing a kind of vibrato effect when you play open strings and rattling... also cos is not touching the fretboard (it's floating in the strings) make the guitar go out of tune if you press the strings down while playing, I have other much cheaper brands with classic clamp design and they work and sound much better than this one, too pricey for what it is tho... pretty but not worth the price.

Works a treat on my Regal - where my previous capo would not cleanly stop all the strings without kinking them.

I don't believe there is a "best product" for capo'ing a squareneck dobro. This one mounts fairly easily on my "spider" dobro, less so on a National Tricone, where the strings are closer to the fretboard.
However the top of the unit is still quite high and can get in the way of playing.