I've never heard of NuJoint, but Cosequin was recommended here. It's been studied & researched on effectiveness & safety. Dasuquin are the same makers as Cosequin.
Cosequin DS More information
When Momo was a pup, he had grade 1 in one knee. I gave them all (since it's a supplement) cosequin sprinkled on top of their food for about a year. It comes in powder form in capsules & is liver flavored, so they liked it. Last vet check, vet couldn't pop Momo's knee out.
He's 6 years old now.