not sure what makes them different or better from the Moog brand. I’ve never had an issue with buying anything from NPD, I’m more just of the opinion that if it ain’t broke don’t fix it. Maybe Rick can tell us what the difference is between the two.My mustang is a 71, and you're right about the Moog parts, they're really good, this will be the 1st time I that I used something else. NPD states that the Rare Parts shafts are a better design HD design, I'm just curious about that. I'll get free UPS shipping thru NPD, so that'll offset some of the cost of the shafts. I went to the Rare Parts website and liked what I read. I'll post results in a couple of weeks.