32 vs. 64 bit Hippos

Hello,

     I am about to purchase another computer and need to
decide between 
32-bit XP Pro and 64-bit XP Pro.  Most of what I will use it
for  will 
use Cygwin.  Does anybody have any (good) experience with 64
bit XP? 
Does it cause any problems with Cygwin?  Does it make
anything better? 
Is there any reason to try 64 bit?

     May the hippos be with you.  Thanks,
       Charles