Odyssey 2: nice and firm. It almost was as firm as the old Saucony Mirage which at times felt like running on dehydrated sponges on the first run. It seems like it has softened up a bit on the last couple of runs - a little more forgiving. I'd give it a 4 of 10 in terms of softness (10 softest).
Clifton 2: really almost squish soft. Too soft for my taste for use as a regular trainer. Maybe a 7.5 of 10 for softness.
Challenger ATR 2: a little softer than the Odyssey 2. I had previously said it was about a 5.5; that seems about right in that it is closer to the Odyssey 2 than the Clifton 2.
Odyssey 2: A pretty locked down feel. Plenty of room for my toes, no hotspots, no sliding around. A bit more structure than the Challenger 2, a lot more than the Clifton 2. A 7 of 10 for structure (10 the most locked down feel).
Clifton 2: About a 4 of 10 for structure. My feet had lots of room to move, perhaps a bit too much.
Challenger ATR 2: 5.5 of 10. A touch less than the Odyssey. More toe room and a softer fee.
Odyssey 2: Maybe the best tongue so far on a Hoka for me. No slip sliding down during the run, substantial enough to provide cushioning. A 9 of 10 (10 being moderately cushioned and stays in place).
Clifton 2: A 7 of 10. Nice cushioning, perhaps a bit too much for my taste. But really slides down during runs.
Challenger ATR 2: A 8 of 10. Much like the Odyssey 2s, maybe a bit thinner. Mostly stays in place with a little slippage.
Odyssey 2: Don't have to tie too tight to keep the upper in place and the tongue from sliding. And they don't come untied. Proper length. A perfect 10.
Clifton 2: I found I couldn't get the laces tied with the proper tension, but the laces pretty much stayed tied. 8/10.
Challenger ATR 2: I have a hard time getting the right tension to keep the tongue in place. It requires using the last eyelet so I can tie a heel loop, but ends up using too much lace. 6.5/10.
Odyssey 2: Feels like the heaviest of the three when running, but doesn't weigh in much heavier. 8.8 oz men's size 9 according to Running Warehouse.
Clifton 2: Says an 8.7 for men's size 9, but it feels much lighter than the Odyssey.
Challenger 2 ATR: 9.8 in men's size 9, according to Running Warehouse, but feels as light if not lighter than the Odyssey.
Odyssey 2: You definitely feel "higher" up than with the Clifton or the Challenger ATR 2. But I was able to run very comfortably on the trail with them. I will consider using them as a trail shoe.
Clifton 2: Because of the marshmallow-y feel, I didn't have a good feel for the ground and didn't love the feel especially on pavement.
Challenger ATR 2: The best of the bunch. I love the ground/trail feel. A pleasure on both road and pavement.
Odyssey 2: Remains to be seen. I haven't noticed any overlay peeling, and they seem well made.
Clifton 2: Not good. Both pairs I had saw the overlays coming off the fabric fairly early in the lifecycle of the shoes - in the first 50-100 miles.
Challenger ATR 2: Fair. I'm getting close to 100 miles running with a good amount of hiking as well, and the fabric on the upper is starting to wear visibly. Hard to imagine getting much more than 250 miles or so before holes start opening up in the uppers.
Odyssey 2 on left, Challenger ATR 2 right: