I've looked at the men's Large Flash 65 and my take is that I got the better pack in the 2007 Cruise UL 60 predecessor.
My UL 60 has the original X'd drawstring compressor tunnels that easily and rapidly compress the load with two top drawstrings, one for front compression , one for back. Nice.
Also, and most important, my UL 60 has NO framesheet but, instead, two tubular aluminum stays, and a Velcro attatching shoulder harness/backpad that I can adjust exactly where I want, depending on the amount of clothing I'm wearing, etc..
I've expanded the cargo space of my pack by adding two REI side pockets for items I'll need on the trail like my toilet and water treatment mesh bags. These side pockets have two vertical compartments each and I've never entirely filled them but it's nice to have the space if needed.
So, yes, I'm happier with my "old" REI lightweight pack than I'd be with the Flash 65. Some things are better left alone.
I DO like the floating, detatachable top lid and bigger belt pockets on the Flash 65 but I'm seam-ripping off my UL 60 top pocket and adding plastic ladder buckles to it and webbing straps to my pack. Then I can detatch the lid and use it as a fanny pack for day hikes by sewing two strips of webbing on the underside of the lid for my belt.