First off... there really is no "Best PDA" out there... it all comes down to what you want to use it for.
If you're trying to decide between PalmOS and PocketPC OS, you can check out this article which helps get an idea of the two:
http://palmtops.about.com/cs/pdafact..._Pocket_PC.htm
Next... sorry, but your PalmOS data will not be able to be backed up onto your PocketPC OS PDA.
However, there is some light at the end of the tunnel... with a little typing and clicking, you can convert most of your data (if not all) over to be used on your Pocket PC.
How, you ask? Well...
<big><strong>Introduction</strong></big></p>
<p align="left"><span style="font-family: serif; font-size: 16px;">So you want convert your Palm <a href="#" style="text-decoration: underline;" #fs2="" class="kLink1" onmouseover="window.clearTimeout(hideTO);showTitle (event, this, 3,'');" target="_new" id="KonaLink3" onclick="OnClick(event,0,this,3,this)" oncontextmenu="return false;" onmouseout=" mouseIsOverLayer = false; mouseOverWhileLoad = false; hideTO = window.setTimeout('checkIfMouseOverLayer()',500);" ><font style="font-weight: 400; font-family: serif; font-size: 16px;" green'#dc="">data</font></a><!-- #DC# --> to your Pocket PC?
Well this FAQ covers how to do that! There are multiple ways to
convert data so you'll have to decide which one you want to use.</span></p>
<p><strong><big>Options:</big></strong></p>
<ol>
<li>Install Outlook 2000/2002 from the Pocket PC. Setup Palm Desktop to sync
with Outlook by installing the
<a target="second" href="http://www.palmone.com/us/support/outlooksupport.html">Chapura
PocketMirror conduit</a><span style="font-family: serif; font-size: 16px;">. Sync the Palm first. Then sync the Pocket PC.
You'll have to disable the Palm sync <a href="#" style="text-decoration: underline;" #fs2="" class="kLink1" onmouseover="window.clearTimeout(hideTO);showTitle (event, this, 4,'');" target="_new" id="KonaLink4" onclick="OnClick(event,0,this,4,this)" oncontextmenu="return false;" onmouseout=" mouseIsOverLayer = false; mouseOverWhileLoad = false; hideTO = window.setTimeout('checkIfMouseOverLayer()',500);" ><font style="font-weight: 400; font-family: serif; font-size: 16px;" green'#dc="">software</font></a><!-- #DC# --> at the time you sync the
Pocket PC if they use the same serial port.</span></li>
<li>Use
<a target="second" href="http://www.stratabase.com/resync/downloads.php">
Resync</a> (currently a free beta) to sync your Palm with Outlook and
then sync with your Pocket PC. See
<a target="_top" href="http://www.pocketpcfaq.com/commentary/myconversion.htm">
My Conversion</a> which covers how to do this.</li>
<li>Install <a href="http://www.extendedsystems.com/ESI/Products/Mobile+Data+Management+Products/PC-Based+Synchronization/default.htm" target="second">ExtendConnect</a>
from Extended Systems. Then sync first with the Palm. Then sync with the
Pocket PC. </li>
<li>Read <a href="http://www.microsoft.com/MOBILE/pocketpc/stepbystep/palm2pocketpc.asp" target="second">Going
from the Palm to the Pocket PC</a> for the option of using the web.</li>
<li>Use the data on the desktop in Palm Desktop. <i>This is best for
users that no longer have their Palm.</i> You can use
one of the three options to import your data from Palm Desktop into
Outlook:<br>
a. You can use
<a target="second" href="http://www.chapura.com/pocketcopy.php">
PocketCopy</a> to convert your Palm Desktop data into Outlook.
This is the easiest way to get your data into Outlook and then onto your
Pocket PC.<br>
b. You can export the Address Book
into a Comma Separated Values format which you can import into Outlook.
Open Palm Desktop, click on the Address icon. Then select File -
Export and then name the file. Also, you need to select CSV format.
Then you can do the reverse in Outlook. Click on File - Import and Export.
Then you can select the Import from another program or file. Select Comma
Separated Values and then you can select where to import the data.
<br>
c. For the Calendar information you can use
<a target="second" href="http://www.lastarks.com/datebookCSV/">
datebookCSV</a> to export it into CSV format and then import it into
Outlook.</li>
</ol>
<p><big><strong>Conclusion</strong></big></p>
<p>While there are multiple options, the first option with PocketMirror
allows you to use both the Palm and the Pocket PC directly with Outlook.
With option 2 you have to purchase and use software to convert.
While option 3 is free, it sends all your data to the web and back to get
it on your Pocket PC.</p>
Source:
http://www.cewindows.net/faqs/convertpalm.htm