I was thinking the same thing but I guess sand isn't that big of a deal really. I guess since they recommend the vented, I will get them then if I don't like them, I'll send em back.
I need about four new sets of boots by February, figured I better start figuring out which ones I am going with. I liked the ones that are almost like a human tennis shoe they worked great but after using them for 2 years then put them up for a couple of years since we didn't need them, they fell apart when I used them again. Plus they were $60 a set. We had four sets, they all did the same thing.
I like the nylon boots for ease of use but they are only good for the sand / grass burrs. The place I need boots for, has Prickly pear and that Cholla or Chulla Cactus, that stuff is mean.