I've got 4 vision stones, 2 v2s and 2 v3s. I've had gurgling issues with all of them. I may have found a solution. It's been 2 days and the gurgling is 95% gone. If this has been discussed before, I appoligize. I basically eliminated the space underneath the drip tip. Take one of those carto mouth piece tips, you know, the ones that come on a carto that we usually replace with a drip tip. Enlarge the hole so it will fit the pertruding tube from the silicon seal. It fits perfectly and leaves no empty space under the drip tip. I don't know why, but it works for me and one of my coworkers.
Greg
Greg