I've used them as well and I also recommend them. They were the cheapest I could find online and the quality is good. I've got them flagged in eBay as a preferred vendor so that I don't forget who I bought them from when it is time to replace. They were pretty hard to get on but once they seated are not going anywhere.
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.