I have tried, lo these many moons, to have an adequate experience using kGTD with my Treo 650 and the Missing Sync 5. This is mainly due to the legacy limitations of the treo.

Lemme 'splain.

First of all, you need Missing Sync. Shut up. You do. iSync doesn't transfer the calendar as the category in the Palm, so you'll get 200 "Unfiled" next actions to sort through in your treo, which sucks. Missing Sync fixes that.

Except, oops! You can only have 15 categories in the Palm! Merlin, I'm looking at your iCal, and you have more than 15 contexts. And so did I, and so will most people.

What happens when you have 17 categories? Well, all the next actions in one of your calendars gets recategorized as "Unfiled," and then when synced back, it's added to the Unfiled calendar. Hooray! You have duplicate next actions to track down and delete! Or, sometimes, they're all changed to Unfiled, which means they can get deleted in kGTD when you sync. Gee!

Don't even get me started on what happens when you've got subscribed calendars. I have 40 copies of some events through 2008 that I'm tracking down and deleting.

Also, there's sync problems with kGTD and the treo, where when you tick something off on the treo, it's not synced back to kGTD, which defeats the purpose, just a little.

Okay, so you've chosen a set of contexts to sync, and it's syncing back to kGTD, and you're ready to keep kGTD and your treo to sync. Ready?

Ideally, this is what happens:

1. "Sync" kGTD, to update your iCal.

2. Hotsync treo.

Does it happen this way? Ha, I say. Ha, and ha again.

Here's what happens.

You bring your treo home, and you've marked off some calls and some errands and stuff at work, so you want to update that. So, you sync it to iCal.

Now you sync kGTD. Which changes stuff in your iCal, because now there are some waiting fors that you've marked off, and oh yeah, you wanted to fix this other thing, and add some more NA's.... okay, sync kGTD again.

Now you need to sync your treo again.

This is the ideal model. Lots of stuff can go wrong. For example, if you sync your kGTD before first syncing your treo, then the iCal actions are newer than the ones in your treo, so they're overwritten. That's always fun.

And when you create a task in the treo? Whee, oh joy. My fingers curl at the thought.

After a very long time of fighting it, I have given up: I print the kGTD todos to index cards.

Nobody should be surprised about that, anyway. :)

In sum: The treo is a nifty phone, but it is far from the ideal GTD experience.

Cheers.