Look and feel
The Cassiopeia and the Aero are a bit more elegant-looking with their metallic, aluminized cases. The Jornada, a bit more industrial looking, is made of heavy plastic, and it feels plenty rugged. The Jornada also sports a see-through plastic cover that is hinged at the top and flips up and around when you need to write on the screen. I would hesitate to toss the Cassiopeia or Aero unprotected into a handbag or carrying case, but not the Jornada. They are all hefty-sized units and feel very solid in hand. I doubt these could be comfortably carried in a shirt pocket.

The screens
The Jornada and Cassiopeia screens are dazzling indoors, but are nearly unusable in direct sunlight. They both offer adjustments for the display, but even at the brightest setting, I found myself constantly turning the unit and my head to get a better viewing angle when outside. The Aero screen does things a bit differently and needs some explaining. By using a TFT, or reflective thin film transistor screen, Compaq claims their screen is perfectly viewable in any light. Outdoors in direct sunlight, I found the Aero to be just that, perfectly viewable. Indoors, without the backlight on, the Aero screen was distressingly dark unless I had a light shining directly on it. Then, it was ultra sharp and crisp. With the backlight on the lower of two settings, (and no other light sources shining directly on the screen), I thought the display was still too dark and found myself searching for a lamp. With the higher of the two backlight settings, I was able to see the screen better without a supplemental light, but kept wishing it could be somewhat brighter. I think Compaq has the best approach to the indoor/outdoor screen problem, but failed to implement their backlight properly.

Battery use
Also, it should be noted that these color screens tend to destroy batteries. I was able to get no more than three or four hours of heavy, consistent use from these units before the low battery warning popped up. I didn't push them much further than that warning to see how long they would go, though the manufacturers claim at least double what I was getting. Be forewarned when traveling.

Other issues
In real world use, each machine will do exactly what you need it to. I made use of the voice recording capabilities quite often for making notes to myself while driving. I did not utilize the stereo headphone capabilities at all, though I gave a quick listen and was impressed with the sound. I also don't play many games, but with their color displays, large storage capacities and stereo headphones, game players will have a ball. Casio makes a big deal over the ability to watch movies on their unit, though I didn't try it. For me, these units are business tools, and to that end they all perform very well.

The palm version of Windows CE does require you to perform many screen taps to get anywhere. Because of that, the manufacturers have included an action wheel and action buttons on these units. These devices allow you to scroll, select, and escape through various menu functions using only one hand. There are also third-party menu applications available that attempt to make switching applications easier as well. The Casio Cassiopeia includes a menu program right out of the box.