I've been skiing in the Garmont Adrenalin for a couple of years and been mostly happy with them. At this point, my main complaints are (a) they sometimes seem to go into walk mode on their own (could also be user error and me catching a pant cuff on the lever, though), (b) I've had to reinstall one of the buckles (rivet failure) and a couple others are working loose, and (c) they don't offer enough skiing performance to effectively turn a pair of GS skis.Having tried on and flexed a pair of Factors, I'm planning on stopping by the local BD dealer tomorrow to write a check and get them thermofit. The flex is a lot closer to my Lange L10s (retail version, flex around 120, I think) than it is to the Adrenalins, although it may be a hair softer; however, given that I'm not lifting three days a week, I expect to get excellent downhill performance out of the Factor while still having the walk mode available. As a ski coach, this is invaluable--I spend a lot of time standing around, and being able to stand up straight is a godsend. Being able to make actual turns in the same pair of boots I can stand around in is a huge bonus (one I initially thought I had found with the Adrenalins, but that was while I was patrolling and skiing mostly mixed conditions; once I started doing more groomer ripping, the shortcomings of the Adrenalins started to become more evident).I see the Dynafity compatability (with the AT sole) an excellent bonus, although I can't afford to switch my AT skis over to Dynafit just yet (and don't want to be unable to ski them while I'm waiting for the AT sole to become more widely available).I had the same problem... I tried on the Factors and the ZZero's and here is what I came up with... The Factors are very comfortable and fit my foot perfctly. They flex was perfect and the boot moved effortlessly in "walk" mode and was like a alpine boot in "ski" mode. The Boa system is great. It allows you to fine tune the fitting to your calf/shin and desired level of tightness. I wish more boots has this feature. Overall, this boot was awesome. The ZZero wasnt the best fit on me. It hurt my shins and didnt seem to move as much as the Factor when in walk mode. Granted it was new in the box and not broken in, but considering that the Factor had no pain whatsoever and being new also, I didnt like the ZZero for the initial unformtable fit. The one pro to the ZZero over the is the light weight. Its a bout 3 lbs lighter than the Factor. I think the uncomfortableness of the ZZero will work its way out when broken in. Overall... The ZZero is more designed for long touring and 100% backcountry use. I would buy this one if that's your intent. However, if you are like the majority of skiers these days who do a little of both and want a "do it all" boot, Then I would definitely go with the Factor. The Factor seems to peform most like an aggresive freeride alpine boot, but can be a good friend on that one day per week that you venture out for a day of skinning or touring. Im going to wait until the second generation Factor's come out next year. My guess is they will work out the 2008 kinks (if there are even any) and keep it the same next year while shaving some weight. Price may go up, but if you are spending $700, is $725 going to really matter?