Per the Costco product description page, my comments are in bold:

Specifications:

• Overall dimensions: 22" H x 14" W x 9.5" D [maybe Costco is including the wheels now, their years-ago measurements didn't]
• Expansion 1" [OMG if it's only a 1" expansion, tolerant airlines might even accept it in "expanded" mode]
• Weight 8.8 lb
• Packing Capacity: 2,726.5 Cubic Inches
• Packing Dimensions: 20.5" H x 14" W x 9.5" D [nice to have interior dimensions; they stay unchanged except height so the wheels and handle probably add 1.5"]
• Linear Cubic Inches: 43.5" [this is smaller than the commonly permitted 45"]

Also of interest: the new soft-sided (unlike the prior polycarb) 22" Kirkland spinner got reviewed online and they measured the spinner variant at 20.2 x 14 x 9.5 inches vs. Costco's claim of 20.2 x 14 x 9.5 inches - on the face of it, Costco calling it 22" is out of sync with Costco's own published measurements. Review online: http://www.reviewed.com/home-outdoor...rry-on-luggage

Since my very first, 1990's "Smuggler" labeled Costco Kirkland weighed a whopping 12 pounds, I welcome the reduction to a claimed 8.8 pounds. The lightest wheelie I've had was 6.6 pounds but that was an LLBean Medium Rolling Adventure Duffle, which is just a toboggan plate/telescoping trolley handle with a nylon fabric duffel top. I have an order in for this new Kirkland and will update my comments when it arrives next week. The most common complaints at Costco's website on the new version are the fact that the "suit folding panel" is only partially removable, thereby taking up space and adding weight; and that the bottom panel is not longer a flat rigid panel, but rather fabric over framing.

I can't help you compare the other bags you mentioned. While I've "strayed" from Kirkland's own now and again, it's hard to beat the quality and ruggedness. A lot of carryon bags work if you never have to check them in. My opinion of the non-polycarb Kirklands 22" bags is that they will hurt the bags next to them before they are hurt by them.