Notion Ink prompting concerns with lack of hardware demo, sky-high return fees [Updated]

We've written a lot about Notion Ink, and – like many of you – gotten very enthusiastic about the potential for a game-changing Android tablet. As with any launch there's controversy, and also good reasons to be concerned, and – while we'd love Adam to be as authentic as anyone else – we're worried by the absence of solid hardware from the company. We're still trying to get information from Notion Ink CEO Rohan Shravran regarding the Adam slate, but right now we believe it's safer – as ever – not to spend money on a device you've not seen.Update: Notion Ink has responded; more information after the cut.

That's in addition to some serious concerns over the fledgling pre-order process, compiled by Android Police, and which details some significant return fees and other processing charges should you decide to return your purchase. Processing for those who did place an order was also an issue, with the Visa payment system going down at several stages and MasterCard not accepted. Notion Ink has blamed a server-side issue in the US and says it will respond to the return fee complaints.

There's also concern over the FCC filing information; Notion Ink has previously said that they had "done something with our FCC application and it will be little difficult for you to find us" but with the filings yet to turn up, it's another omission that's raising red flags. We've asked the company for links the filings so that we can confirm that Adam has, indeed, been through the FCC.

In short, while the appeal of Adam on paper is high, and the prototypes the company has shown previously have had promise, we're not convinced that – these concerns outstanding – it's the time to put money down for a tablet from Notion Ink. We're hoping the company can disprove our concerns, and will update when we hear from them, but now is definitely the time to be cautious with how you spend your money.

Update: CrunchGear is saying the same thing: now is the time to keep your money in your pocket until we have more information.Update: Notion Ink has responded, blaming MasterCard's long application process for their absence in the payments options, and suggesting that Indian card processing company CCAvenue was seeing problems with declined payments from US customers and server time-outs. The company says it is also planning to demo Adam on video and in-depth on December 18th.

As for the FCC filing, it seems Adam is still yet to receive approval – that's expected, the company says, in the latter third of December 2010. The return fees, they argue, are on a par with what Dell charges for restocking.

In short, Notion Ink suggests holding off on ordering if you're cautious, which fits in with our advice as well. We'll update as we hear more.