The ElkUSA petburger is a higher percentage of offal and it's leaner but you can't taste the offal at all. I'm not sure if the skin is still on the tongue or not but I have never run across any recognizable taste bud bits.
I kind of like the fattier USWM petburger. But if someone wasn't a fan of fat, the ElkUSA might be better. They were out of stock on it for a while and so I bought a huge bulk order from USWM but I still like both.