I used to write many of my columns on my HP iPaq palmtop organizer. Instead of waiting for Windows to start up on my slow-booting laptop computer, I'd take advantage of the iPaq's instant-on capabilities. It was particularly handy while riding the subway or as a passenger in a car, because I could attach a stand-alone QWERTY keyboard in seconds and start writing immediately.

When my iPaq died, I moved back to mobile composing on my laptop, despite the extra overhead of slow startups and shutdowns. But with the introduction of several new BlackBerry SmartPhones, I thought I would try palmtop writing once again.

The key is that Research In Motion (RIM), the Canadian company behind the BlackBerry, has decided to include Documents To Go on its latest SmartPhones, including the Blackberry Bold and the Blackberry Storm. Documents To Go is a set of software applications that simulate Microsoft Word, Excel and PowerPoint on palmtop organizers and SmartPhones. The Bold is offered by AT&T, the Storm by Verizon Wireless, both via exclusive arrangements with RIM.

These phones both have on-board keyboards -- a tiny but full QWERTY hard keyboard on the Bold, and a new touch screen technology on the Storm. That's how I wrote the column you are now reading.

My candid assessment is that either BlackBerry will do the job in a pinch, but I don't plan to make a habit of using either one to create long documents.

Over the past few years, I've gotten used to the small buttons on palmtop devices like the one on the Bold and actually have gotten good at writing short text messages. But writing 600 words at a sitting is much more difficult.

Similarly, using the Storm's new touch screen slowed me down considerably. I like the new tactile design of the touch screen, but I tired of it way before I had the column complete.

The touch screen on the Storm has been getting rave reviews because you can feel the buttons much better than on normal touch screens. I like the way each onscreen keyboard key lights up blue to indicate that you touched the right key. But my fingertips are larger than the keys and press the wrong one too often, especially when typing fast -- a common problem with onscreen keyboards.

The screen automatically changes between portrait and landscape orientation whenever you rotate the phone by 90 degrees -- a nice iPod-like touch. But the cool factor doesn't make up for the need to type slower as you wait for the onscreen keyboard to catch up with your fingers.

When in landscape mode it shows a 35-key QWERTY keyboard. Change to portrait and it becomes BlackBerry's SureType keyboard where two letters share each key, just like on the BlackBerry Pearl. That shared key arrangement works better than you'd think because it automatically suggests words from your dictionary and names from your contact list as you type. It picked up almost all my words. But I still had to proofread extra hard.

Finishing my column took me an extra 45 minutes. It probably would have been longer if I hadn't switched midstream to my desktop PC.

So I'll stick to my PC for most of my writing. When composing with a phone, I'll go back to using a full-size add-on Bluetooth keyboard instead of the built-in keyboards on the phones. That would be using the right tool for the job -- just like my parents taught me.