The point I was trying to make is not that they're hit-and-run merchants, but since we enjoy buying Chinese merchandise, the Chinese in the US have started to sell it semi-directly to us, a lot cheaper. They have the contacts in China to get a supply, they can see what West Marine is importing (and selling,) and being good businessmen, now sell directly to us. Rancho Santa Margarita (misspelled Rancho STAN MARG,) is the town in which they live and get their e-mail, their warehouse is probably nearby (if they even have one.) The web site reflects that they are doing this themselves, English is not their first language and they're not hiring some professional. This keeps their overhead and prices low, and they can undercut West Marine substantially, even other web-only suppliers. Remember the Chinese love to do business, not work for West Marine.
You can find the same type of web sites for electronic components and specialty auto parts. Some of those sites sell directly from China, the days order is air freighted to the USA and then broken up and the individual orders sent via USPS. I've ordered that way and it was even cheaper, minimal overhead in the US. And they make sure that you get the correct part, even if it takes a couple of shipments. The danger with overseas sales is credit card fraud, where someone rips off the card info and uses it, as happened to me. (The credit card company caught it and gave me a new card, but I'm not going that route again.)
This brings up the question of what will happen to our established dealers. Look at what happened to book stores, a lot of new book stores are closing down, and books now largely sell through Amazon, etc. Will the existing cheap web sites with web sales only be able to compete with direct importers operating out of their homes? Most of our electronics and marine hardware comes from China, so why not use the web to sell directly? I don't claim to know what will happen and it'll be fascinating to watch. I order a heck of a lot via the web because it's easier, cheaper and if you order a brand name, you know what you're getting, such as Honda parts. With marinepartdepot.com, there have been a couple of recommendations (see above,) and certainly more of us will follow.
As far as their guarantee, since the stuff is so cheap to them, they're not going to quibble with you. They'll just send you a new part. They want to do business, not get a bad rap. At least not now, when they're getting started.
Boris