This will definitely keep my feet cool and dry this summer. I wore it for a week when it was in the 80s to give it a test run. A few things first. These definitely run larger. Probably 1/2 to 3/4 of a size larger. So, if you're in between sizes, go a size down. Keep in mind, if you're not going to be wearing socks, you'll definitely want to size down if you're in between sizes.

Another issue is that after 3 days of wearing these (12 hour days in a kitchen), the top left part of my left foot was becoming extra sensitive due to scraping.

I decided to punch the holes on the side to keep my feet ventilated. Without the holes there, my foot was getting really hot & sweaty. With the holes in place, it made a world of difference!

Grease & water weren't an issue. The grip was very comparable to your average restaurant shoes. The only time I had issues was when the entire floor was completely soaked. But then again, that's with most shoes.