I've never ordered from rainbow, but I think next time I order(which I very rarely do since I have a shed full of feeders lol) I'll try rainbow.
This isn't a shot at Josh's frogs or anywhere else, but they also sell bandeds, and they are definitely better than regulars, but I have noticed the ghanns crickets are even less smelly and live longer than the others. I'm not sure if something they're doing is making the crickets healthier, that other places aren't aware of or what, but I haven't been able to match them in quality from anywhere else. Makes me sleep well knowing my animals will likely not get parasites from them too since i don't think they deal with any reptiles in their facilities(which is always a risk, even small, with places that do).
That all said, ghanns are more expensive, and for my 1 chameleon on special occasions. I'd still happily buy crickets from rainbow, Josh's frogs, etc. They're still at a much higher quality than the others and you shouldn't have problems with die off or smell. I think if I had a large collection that needed regular cricket feedings, I'd spend the little extra on ghanns for the quality though.