Using internal site search vs url?

In PPC campaigns for an e-commerce site, we have them set up to use internal site search w/keyword search term as opposed to manually setting up a final URL.

Should we in fact be setting up a final url instead to gain any SEO benefit of users going to that page and ultimately buying?

Just curious what experimentation others have done so see if there is infact a correlation with PPC, and increase of traffic and conversion from googles perspective.