O...
MY...
GOD...

Three words... MUCH MORE PREDICTABLE AND PRECISE...
Okay, that was five words. So sue me...
Basically, I feel like I upgraded the suspension from an American luxury car with a "squishy comfortable" ride to a finely-tuned European sport car with precision handling.
As soon as I got on the SERG, I noticed the difference. The bike didn't "squat" so much with I mounted up. I'm a relatively heavy guy at 250+/-. The stock shocks and forks squashed a lot when I got on. The AK-20s and Bitbuos... they don't...
Driving out on Rope Mill Pkwy, I coiuld immediately tell that everything was "tighter."
When I made the left off of Sixes Rd onto the I-575 South entrance ramp, I had my first "OMIGOD!" moment. This turn is a downhill left-hander. The road surface is off-camber. I leaned into the turn like I always have... and the front end felt like it scooted to the right an inch or two. As my heart skipped a beat or two, I straightened her up just a little and got on the throttle.
On the 250-mile ride home, there were a lot of little revelations about how different this bike rides now.
- Bumps encountered at speed are not nearly as "bone-rattling" as they once were.
- The bike now responds marvelously to much more subtle input. It's almost "you think about it and the bike does it."
- The bike seems even more stable at high speeds. I rode 75-95mph most of the way home. The little front-end wiggle I'd been getting above 85mph is almost completely gone. What's left I attribute to the Avon Cobra skins. They are radials, but not quite as good a ride as the D407s.
- The bike doesn't nose-dive when breaking even in a quick-stop. AMAZING! It also does not squat so hard when accelerating.
Another great investment in these bikes. Thanks everyone for the tips.