Does anyone use a fluid bed sluice like a Bazooka or a Green Mountain gold trap? I have heard both views - that they are great for fine gold recovery, or not. I'm wondering if anyone has any first hand experience.

These links are examples, not necessarily endorsements:
 https://snakeriverproducts.com/product/recon/ 

 https://greenmountaingoldtrap.com/3-long-ez-cleanout-river-bed-hog/ 

TIA