ARIATMen's Lookout Boot

Will the soles hold up to long mesquite thorns?

how stiff is the back heel? Or is it soft leather for the heel...and up from the heel to ankle?

How are these for summer wear? As a "lookout" style are these insulated and intended for winter?

I wear size 9 in most work boots and size 9.5 in tennis shoes. What size should i go with?