Do you ever compare your gps track board up/board down? That's my best way to see what sort of lift I'm getting. It's not all that scientific, but I often find a readable increase.

On an apples to apples comparison of centerboards, or deep vs shoal draft, the difference is pretty minimal. That's obvious just checking phrf handicap allowances for various boats racing shoal vs deep. All these items including foils and things, look pretty dramatic as whole on a completely new racing design boat, but taken singly, I don't believe they are even near the hype that boat designers and builders would have you believe in the advertising.

Your last paragraphs are what resonate with me. There are so many times that the centerboard has put me in a better spot to anchor, sometimes the only one available. After you've sailed with that, it would be hard to give up.