I’m thinking about buying one of these for my Yam 620 bass. I’ve been using a Get A Grip and an ergobone, but it seems the Rath or the Hagmann should work for me, and given the Rath is much less expensive than the Hagmann, I am thinking to give the Rath a try. How fussy is it to install and use?

I find that the Rath works well for me on my horn, can't comment how it works for you or with a Yamaha. A big factor is whether it can fit your case/ gigbag when assembled. If it does then there there is no fuss-factor. If you need to take it apart, that is not something you want to do on a daily basis.

I have a Rath hand brace. I like it.

I also use a elbow rest I made to put my left elbow on.

I had my tech alter the brace so it fits on my Edwards valve brace rather then the bell brace so if I change bells the brace stays put.

I was able to install the brace so it fits in my Edwards tan case. The gig bag was an easy fit.

The elbow stand is a cymbal stand with an 8 inch round board covered in padding and cloth.