I'm not convinced the Zflex isn't a scam. Oh the product is real all right there are a dozen chinese companies selling it. This one has yet to ship tho. If I don't get it soon I'm having AMEX reverse the charges.
I generally prefer to use Amex myself for any transactions (especially anything significant) that carry some extra risk... and they have never let me down. Used to do all my eBay purchases that way... though I have switched to my other CCs more recently (at least for smaller purchases or from particularly reputable sellers).
Also usually used PayPal on top if possible, but never really trusted their system to settle issues. The only one (and recent) time I deferred to PayPal to settle a case (for something small similar to your transaction) they failed me pretty badly, so I won't be doing that again.