When we started discussing the Sony Reader last week we described it as a slick piece of hardware and outlined its fabulous display technology from E Ink. This week we'll look at the rest of the system.

As we noted, the Reader is paperback sized. On one side is a power switch, a volume control and a covered socket for a Sony Memory Stick or an Secure Digital Card.

On the adjacent side is the charging jack for the rechargeable lithium-ion battery (enough power for a remarkable 7,500 "page turns"), a socket for the docking station (an extra purchase), a USB socket for data transfer and battery recharging, and a headphone jack.

The physical user interface of the Reader has 16 buttons. This is a mistake - an electronic book should be as simple as a real book but with more functionality. The Reader fails in the first goal and overdoes it in the second. While a touchscreen interface would have been preferable, the physical controls are too numerous.

The Reader stores content in its internal 64MB flash memory or one of the optional memory cards. Supported content formats include Sony's proprietary BBeB Book format, Adobe PDF documents, text and RTF files, and JPEG, GIF, PNG and BMP images. It also can play MP3 files (AAC files can be imported) while you read. We won't go into the audio support other than to note that it's no iPod - not much volume, no equalizer, no playlists . . . you get the idea.

The BBeB Book format comes in unprotected and DRM-protected versions, and Sony's Connect eBooks store offers more than 10,000 titles at 20% to 25% discount over the dead tree versions.

The Reader also can handle RSS feeds and here's where we start to get into the flaws of the product. Sony only lets you subscribe to a list of feeds it provides. These are useful choices such as Engadget and Wired News, but should you want to add, say, Gibbsblog, you are out of luck.

So what of the Reader's performance? Poor. With half-second page refreshes in black-and-white mode the lag between pressing a button and something happening is annoying. Sure, you get used to it but the lag is a drag.

Another issue: There's a button that provides small, medium and large text rendering (as well as rotating the screen orientation), all of which work for eBooks and text files but only small ("fit width") and medium ("fit page") are available for PDFs. This is a problem for documents that are, for example, formatted to three columns for legal-sized paper - you can't zoom in to see the text.