I have actual experience with the Kenda tires. When I first got the bike it had brand new Kendas front and rear on it. The rear lasted only 4000 miles, then I put another one on that REALLY wore out after only 4000 miles.
How was the gripping and traction? Personally, I will sacrifice longevity for traction, especially in the rain.
From my personal experience, Avons were the longest lasting tire I've ever had on the CX, almost 15k miles before I needed to replace it. Traction...acceptable but a bit dangerous in the twisties when it rained. Best tires (both automotive and bike) for grip and rain have been Dunlop D's, although they didn't last anywhere near as long as the Avons.