Sandals are well named (if not well-spelled). They certainly do fill up with sand and grit so that you have to stop frequently to empty them out (a more arduous task for me these days because of my arthritis) but they are much cooler for walking in hot weather. My personal choice are these Keen Newport H2s. (My wife Della seems happy with her couple of pairs too): http://www.keenfootwear.com/us/en/product/shoes/men/waterfront/newport%20h2
I have weighed the Newports (422g) and the Arroyo 2 (411g) each (in US size 9). Probably the Arroyo is a better trail sandal.