What is your preference, and why?
I'm pretty sure I've had both, and iirc the Moog has a nicer, thicker rubber boot. I generally like Moog parts because a lot of them are "problem-solver". However, Raybestos are usually pretty good as well.
Moog for me. I had a bunch of 2 year old Spicer (Raybestos) stuff go south on me last summer and it left a bad taste in my mouth. I installed Moog and a year later and double the mileaI heard ge as before no issues. I heard that Raybestos started taking a percent of their parts and reboxing over seas product. No good source, but somethign I heard out there.
Moog generally has higher quality parts. I started with bad upper joints and this replacement became my first job on this vehicle. Picked Moog over Mevotech and Ingalls. I've never heard of Raybestos and judging from what has been said here, I don't want them either.
OK, but were these an old re-badged Spicer product or the new ones with synthetic bearings?
Look on the box AND the part to see where it's from before buying if possible