My Adorence (Balam knock-off) works ok, but tends to slide down unless you have it adjusted perfectly. If your bass is anything like mine, it will use a relatively short strap.
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I personally play bass with no strap or harness at all. I always play seated with the sax resting on my lap. I've played hundreds of hours and dozens of gigs that way. Works great. Another thing that makes playing it a lot more comfortable for me is to not use the R thumb rest at all, rather rest my thumb on the alt-F# rod. I got the idea from Bert Brandsma who does the same thing. I'm a big guy with large hands, but using the R thumb rest causes significant discomfort after several hours of playing.
If I were marching in the Mummers, I'd probably use something very substantial like a bass drum harness.
You'll probably need a stand too. I use a cheap bari stand with a couple of modifications - bend open the top and drill a new hole for the bottom support. Otherwise you'll have to spend another small fortune on a bass stand.
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