Whilst reading Hacker News at ycombinator dot com I came across the following piece from an experience Amazon FPS user. I have to say I’m not surprised, and mentioned briefly in a previous blog posting about how Amazon’s success is still in limbo (at least in this category dominated by Auth.net and others)

The requirement of an Amazon account is crazy, talk about a hurdle pre-checkout!

clipped from news.ycombinator.com

Experience with Amazon Flexible Payment Service
Just wanted to share (I know this topic is all time popular) about our experinece with Amazon FPS.
First of all, we charge a small subscription fee each month. This severely limited our abilities to cherry pick payment processors. Second, we did not want to deal with (store on our servers) sensitive data such as credit card numbers.
From a technical point of view FPS is a bit too complicated. Definitely more so than other gateways we looked at. That is because it’s too generic: instead of 2 perties there are always 3. “Build your own PayPal!” is their idea. For people who aren’t building their own paypal it is a bit annoying.
Secondly, your users must have Amazon accounts. That may be good and bad, depending on how you look at it. To us it was bad: we did not want people to see “Amazon” stuff during sign up process – we had some unpleasant experience with similar approach taken by PayPal.

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