5" speakers that fit 1st Gen. Avalons

[KeepItSimple]

Hello I have a '95 Avalon XL with the 4 speaker system. I understand that they take 4" replacements but on Crutchfield they show the Polk db501 5" 2-way speakers as a match.

On the Polk website part of the description for the db501 says 'New Size 5 inch design affords easy installation into OEM factory spaces'.
http://www.polkaudio.com/caraudio/pr...akers/5/db501/

Does anyone know about these and wouldn't 5" be much better than 4" or just a little better?
I'm hoping that maybe it would have enough bass so I wouldn't have to install a subwoofer.
The highs sounds great with my new stereo (no external amp) and factory speakers but the bass is lacking.

[KeepItSimple]

sorry about the same question 3 times. my browser was hanging up and I didn't think anything was posting.