There's much to like about the GP4000's, notably longevity and rollout. Very uniform tire and easy to mount.
But I'm a bit of a cornering demon, and the Conti's fall short of the Michelin Pro4, wet or dry. (Guessing same for their new Power, too.)
At the same 100 psi, the Pro4's feel superior, without the need to drop down to ridiculously low psi's and risk pinch flats.
Stocked up on the Conti's a year ago after finding around $30 apiece. Plan to return to the Michelin fold once my supply runs out by Fall.
Funny that. I hate the Michelin's on corners and have crashed twice on dry Spanish roads on Pro Race 2's so that pit me off. The Power Competitions feels pretty much the same. I find the GP4000’s incredibly grippy (the ones with Black Chili) and have never had a moment wet or dry. I'm quite light which may make possibly a difference?
PR2's are so ten years ago, man. PR4's are vastly superior, in my opinion. Slicks = more rubber on the road. Not sure what the Conti tread pattern accomplishes, other than equating to less of a contact patch in corners.
Like others mentioned here, I suffered a slit sidewall (mine from a one-inch rounded rock) on my rear 4000 25c tire, less than 500km into its life. Very brittle sidewalls. Compare this to sidewalls of any of the Pro Race series, which are more flexible and utilize a woven pattern within the compound. Never experienced such a sidewall failure in almost 200,000km of Pro Race riding!
Overall, I think they over-hype this rolling resistance thing. Conti GP4000's are fine, but I think better choices exist.