I think from memory we did a BT speaker sound-off between my little Anker one and a bigger JBL one awhile back when camping. The JBL one was much bassier, which is kind of their thing I think. Was a bit much for my tastes, but if that's important then bigger is always going to be better. I think the consensus was that the JBL sounded bigger/better, but the Anker was better value and not far off in sound despite being half the size/cost.
Just seen there's a new range of Anker Soundcore 'Boom' speakers that sit above my little one. Seem a bit more targeted at the JBL customers and a bit more 'big party sound' with some quite cool features like self-righting and floating in water to be played in pools. Which obviously would only be relevant in your man shed after a significant plumbing issue. Edit: Also just noticed you mentioned these in your original post so know about them
TBH, I don't think you can go wrong with any of them these days, and especially the bigger brands like JBL and Anker. Just pick the features you want and budget.