What is Dueler H/L 422 Ecopia?
Dueler H/L 422 Ecopia is a new tire from Bridgestone that debuted in 2010. It’s a new member of a fuel efficient Ecopia family of tires. 
It's a very low rolling resistant all season tire for SUVs available in few sizes ranging from R16 to R18. Depending on a size, 422 is rated 99-112 (load), S-V (speed), and 640AA (UTQG tread life/traction/temperature).
The tread is identical to Bridgestone’s Ecopia EP422 tire and I believe Dueler H/L 422 Ecopia is a bigger (SUV) version of the smaller, passenger car size Ecopia EP422.

What is so great about Ecopia?
This is a new "green" line of tires from Bridgestone. The studies I've seen published on Ecopia tires indicate 30-40% reduction in rolling resistance translating to 3-4% total MPG improvement compared to ordinary tires. That difference is small and hard to measure in every-day's driving, but cumulative and can save up to $400 in gas (or more if fuel prices keep going up) over the lifespan of tires, partially paying for the cost of tires. Thus there is no good reason to buy non-low rolling resistance tires if one can get same or better performance in low rolling resistance tires if one looks around.
According to Bridgestone, Dueler H/L 422 Ecopia’s comfort is as good as their very good benchmark conventional tire Dueler H/L Alenza with traction only slightly below that of Alenza. Ecopia is more fuel efficient due to lower weight, soft sidewall, and use of silica filler in tread compound.
I have OEM Ecopia EP20 tires in my Toyota Prius and I like them a lot (I reviewed them on Epinions already). Based on my experience with Ecopia EP20, I checked if Ecopia was available in size 225/65R17 for my RAV4. It was and that was good enough for me to go out and get those tires even though very few reviews are available on Dueler H/L 422 Ecopia.

My take on new tires.
The difference was apparent in the very first drive from a tire place. Less tire noise. The original OEM Yokohama Geolandar G91A were never quiet and got more noisy with age. RAV4 has no enough noise insulation and one can hear it easily. The only significant tire noise that could be heard at hwy speeds is on rough asphalt. I hope Dueler H/L 422 Ecopia will not become noisier with wear (I does happen a lot with tires though).  Dry traction is great and the handling is crisp and quick when tires inflated to 38-40 PSI. I had a few emergency maneuvers on hwy and the tires were very responsive. I did not get to use them in a heavy rain or snow, but expect no problems (will update after an upcoming major travel).
So far, hwy trips yielded the same MPG as OEM tires. This is actually good news as new tires have usually a small MPG penalty over old, worn tires (difference in tread size and hardness of used rubber).
The high tread life rating (640) should provide for a long life. The tires are warranted for 5 Years / 65,000 Miles.

The negative.
Cost: they are slightly more expensive that conventional tires in the same size. Dueler H/L Alenza would cost $30 less per tire. I hope to recuperate that and more in gas savings.

Recommended: Yes

Amount Paid (US$): 180