The other day, I ran my 10 times 30-second intervals in my VFF Flows (instead of my KSOs) with a pair of Injiji toe socks. It was 2 degrees Celsius. It was a really good choice of footwear.
I noticed some differences between my KSOs and Flows: The Flows are MUCH warmer (which is a good thing because I forgot how cold 2oC feels like). They feel like they have a thicker sole (although that could have been the socks, too). They are less flexible, probably because of the neoprene as opposed to the thinner synthetic material of the KSOs. And they were more wind-resistant.
I also noticed that my running gait is exactly the same between the two VFF models.
Another thing I noticed during this run, unrelated to the shoes I chose to wear, is that my right leg is much weaker than my left leg. My right leg tended to hit the ground louder/harder than the left, which is very noticeable with a springy, midfoot running gait. Guess that right leg has some catching up to do now that (hopefully all) the nerves are awake now.
The snow hasn't stuck around yet so I can continue to run outside in my VFFs. When the snow stays, though, it's off to the indoor track to run without shoes.