Buying an HP tablet: Vista 32 bit or 64 bit?

[Uniqueuponhim]

I'm buying a customizable HP tablet from costco, and I was wondering whether or not it would be worth it to upgrade to vista 64-bit from 32-bit. The upgrade is free, but from what I have heard, Vista 64 has a lot of trouble with drivers, and runs 32-bit software poorly. On the other hand, since it is a laptop, HP should be able to provide all of the proper 64-bit drivers and I shouldn't have the same troubles that I would with a desktop. Getting Vista 64-bit would also enable me to have 4GB of RAM instead of 3.

So, how much of an increase in performance is there with Vista 64-bit over 32-bit (with the same amount of RAM)? How much of a difference in speed will I notice if I have 64-bit vista AND 4GB of RAM instead of 3? Are there any driver problems with HP tablets and Vista 64? Is it worth the hassle? If I do go 64-bit, is the extra GB of RAM worth $98?