I JUST got my dubias today and i already like them better than crickets. There is absolutely 0 smell, just the smell of the food the supplier gave me. They seem very hardy and aren't terribly quick moving. I've found they play dead when bothered. They also come in a ton of sizes which makes feeding different animals easy. I've only got a crested gecko and 2 leopard geckos. I figure I can freeze, trade or sell extra roaches as i produce them.
One thing i REALLY am liking about the dubia is that they are sexually dimorphic. The males have large visible full body wings and the females have little wing nubs. I don't have to touch them to sex them at all. At least 3 of the nymphs that I was shipped molted into adults over the last few hours which is sweet because there were NO adults in my order. Im basically going to leave them alone for the next 30 days and see what happens.
Oh i have also found that the very small nymphs can get enough static to climb their plastic tub a bit. I put a layer of foil tape around the inside top of the tub and that thwarts any escape efforts quickly.