Help buying PC for Vista

I appreciate anyone's help with decisions regarding new PCs and future
Vista compatibility.

I am trying to decide between two Sony laptops - the new VGN-TX750P/B and
the new VAIO SZ120P/B.

I hear that the Duo processor in the SZ machine will work better, but I like
the
portability of the TX laptop.

Any clarifications regarding the ability of the Pentium M 1.2GHz in the TX
to handle the new Vista platform would be helpful. FYI, the Sony TX has a
label
that states it is compatible with Vista, but the salesman at CompUSA
strongly recommends the SZ laptop.

Also, if I do go with the SZ series, it isn't clear if the Video/Graphics
capabilities of the 120 model are sufficient or if the 160 unit is better
(you can see a comparison of the specs on CompUSA's website).

Again, any help would be most appreciated. I plan to make my purchase
decision today.

Thanks!

Bix