I couldn't find my arm warmers for a ride recently, and a friend loaned me a pair of these. Loved them, and was really happy that my wife got me a pair as an anniversary present.
I've always liked my synthetic warmers, but merino wool warmers are so much nicer. You don't get that clammy feeling from natural fibers that you can get from synthetic.
I also like the thumb loops on these. I thought they might interfere with my cycling gloves a little but the did not. If anything, maybe you get a little more cush from them. I wore them to run a 10k this weekend, and I would have started the race with gloves on, and these let me go gloveless.
These are comfy, functional, and they're a great deal.