Concerns are growing over start-up Notion Ink, with the company yet to show hardware of its Adam tablet – which went up for pre-order yesterday – and issues over payment processing and potential return and restocking fees. Despite months of marketing, the Adam tablet went up for order without any hardware demonstration, and while we’d like to see a potential game-changer enter the marketplace, that also makes us cautious.

AndroidPolice dug through the returns policy and turned up some very high restocking fees and strict conditions; Notion Ink says it will respond, but until it does we’d recommend keeping your money in your pocket.

Update: Notion Ink has responded this morning; more information at SlashGear.