I've purchased a couple of slabbed coins from them in the past. The transactions weren't all that memorable, which is a Good Thing. Don't expect bargains -- I paid solid prices for solid coins.
I have done business with RCNH for quite some time now. Two thumbs up from me. One of the better dealers, IMO, who will cater to virtually any level of collecting. I work with Paul B.
I agree that they're a dependable respected company. Their website isn't much to talk about, but you can get on their mailing list.
Very honest and ethical, but don't expect bargains from professionals who really know their stuff. Warren Mills is a former grader, the rest of the staff are all very knowledgeable and generally helpful but sqeazed in a recession economy where the focus has shifted from certified coins to bullion for many. So you have clients calling them up to sell coins back to them, one challenge of the coin business. I asked Paul to price a coin at a show that was worth over $2000 once, he made an honest mistake quoting me under $800. I did not hold him to it since it would not have been fair under the circumstances. Ethics and honesty comes with a price tag in business; those who are exposed for selling doctored coins or ripping others off can become powerful enemies.