Meg is 17.75" (36 ish lbs); Gusto is 17.38" (28 ish lbs)
I run both is regular AKC/CPE and in performance USDAA, so they jump 16" everywhere. I'm ready and willing to drop Meg down to 12" in all venues (Preferred AKC/Veterans USDAA/whatever they call it in CPE) as soon as she gives me a sign that she needs it.
Both of mine were initially on the low end of the 22" jump height for USDAA. I chose to run them performance for a few reasons.
With Meg, she isn't incredibly well built, although she's proven to be very sound. She also has a bad scar on one elbow that she had when I got her. I never expected to be very competitive with her, so jumping her a little lower just seemed like a good idea. I just started her there and we stayed in it.
With Gusto, I initially figured we wouldn't be dealing with any physical issues (surprise!). I made the decision because he was so close to the bottom of the jump height - and because I didn't think he'd be competitive in 22" Championship. I don't train hard or seriously enough to think I could reasonably get Super Qs and Steeplechase placements among the dogs and handlers in that height class, who are arguably the most competitive. And I wanted to be able to be successful.
Now, he actually qualifies for the new 18" Championship height, and I gave it a lot of thought. It's actually (here, anyway) probably less competitive than 16" performance. I'd have been comfortable with him jumping 18" for sure, even with the elbow issue (although this was all thought out before he went lame). But the spreads are BIG and the increased a-frame height gave me more pause. He also had a really hard time dealing with getting measured (no bite risk, but he really doesn't like strangers putting their hands on him), and I didn't want to have to deal with a new set of measurements. I'm happy with him in performance.