These are what I use in the Rocky Mountain backcountry on days when I can wet wade and also for trail stream crossings. They're fantastic. They obviously allow a little grit and gravel to get under your feet, but I've spent many a warm day fishing in the mountains and it never was too bad of a problem. I would stop and clean them out but only during normal breaks. And they do weigh right at 1.5 pounds for the pair. They also look great around town and are extremely comfortable.....I even wore mine on the plane once.
I just ordered another pair but two sizes too big. I plan on using them with Orvis stocking foot hippers that weigh 1.5 pounds as well. I'll have great wading ability in the backcountry with only a three pound punishment.
Here are mine strapped to my backpack. They are North Face Hedgefrog sandals The North Face Hedgefrog II Sandals - Men's - FREE SHIPPING