A new portable satellite radio recently hit the market -- the XMp3. It arrives at an odd time, now that America's two satellite radio companies, XM and Sirius, have merged into Sirius XM Radio. The XMp3 stands in a class of its own in terms of cool features, but it has the distinct feel of a radio designed prior to the merger. It was born with one big flaw.

A new portable satellite radio recently hit the market -- the XMp3.

It arrives at an odd time, now that America's two satellite radio companies, XM and Sirius, have merged into Sirius XM Radio. The XMp3 stands in a class of its own in terms of cool features, but it has the distinct feel of a radio designed prior to the merger. It was born with one big flaw.

First, let's welcome XMp3 for its multitude of innovations. This gadget (available at Best Buy for $280) is a pocket-size satellite radio that tips the scales at just over three ounces. Made by Pioneer, it's a superior successor to the company's first portable radio, the Inno.

The XMp3 has 2 GB of on-board storage and a slot for a microSD that can hold up to another 8 GB of music or audiobooks. The Inno had 1 GB of storage.

The XMp3 can buffer the most recent 30 minutes of live programming, allowing you to pause, rewind or fast-forward whatever channel is currently playing. The Inno had no such feature.

The XMp3 can record five XM radio channels at once and store 100 hours of programming. The Inno recorded one channel and could only store 50 hours.

The XMp3 auto-records channels you listen to most often so you're never without XM Radio, even when you can't pick up a signal. It also features a program guide that tells you what's coming up in the next couple weeks. The Inno had neither feature.

So what's not to like about the XMp3? Well, XM and Sirius signals are each beamed from a separate set of satellites. To date, no radio can pick up both sets of signals. Someday, the new Sirius XM Radio will sell radios that pick up signals from either set of satellites. Unfortunately, the XMp3 is not that radio.

The "XM Everything Plus The Best of Sirius" programming package ($15 a month) lets the XMp3 tune to 11 Sirius channels, including Howard Stern, NASCAR and NFL Football. For now, though, that's all you get of Sirius' 130 channels.

As a fan of the many features never before offered by a satellite radio, I bought the XMp3 last weekend. But I have no doubt this gadget will quickly become outmoded by radios that tune to both XM and Sirius, not to mention ones that have more advanced features.

To us early adopters, buying the XMp3 makes great sense. Most everyone else is likely to disagree.