Yes, I've used them. No, I wouldn't do it again, nor recommend them.
I placed a big order to do the front end of my Challenger (calipers, rotors, wheel bearings, dust seals, master cylinder...). They accepted the order, then emailed me to say that the calipers were not available, but I could send mine for rebuild, or wait for new ones (with no guarantee about accepting my cores). I got one new one (an original K-H style), and then I sourced the other locally. Rock Auto ended up being more expensive than my local Murray's Auto.
But the biggest problem was shipping. They just threw the parts into whatever boxes they could find, with NO packing material. My bearings and dust seals were thrown into a Lucas Oil box, and my caliper and master cylinder were thrown into a Valvoline box. The rotors were each tossed into different types of boxes. Again, there was NO packing material in ANY of the boxes...NONE. Needless to say, the parts arrived here a mess. One rotor had broken the box and was laying on my front porch, and the other rotor had smashed another box, destroying the dust seals. The master cylinder was all scratched up, the booster was dented, and there was cardboard 'dust' all through it, from the box it had chewed up.
I contacted RA, and was told to send pictures of the damage, which I did immediately (including one picture showing the destroyed boxes on my porch, before I even touched them). After several rounds of phone calls and emails, RA decided that there was not sufficient 'proof' that the parts were damaged in shipment. So they told me I could ship them back...AT MY EXPENSE, and they would 'determine whether they thought the parts were damaged in shipment'. Of course, I showed the pictures to the shipper (UPS, I think), and they wouldn't help, because the parts were 'not packaged properly'.
I went several more rounds with their 'customer service' group, and finally decided they were not going to stand behind their ridiculous shipping methods. For what it would have cost me to ship the damaged parts back, I was able to replace them at a local store. From that point, I decided to support my local auto parts stores, and forget the 'low price' I saw online. Lesson learned.
-Tom
