Clean URL: with or without "?"

Question

Simple question

What is better:

http://www.example.com/product/123/subpage/456.html

or

http://www.example.com/product?123/subpage/456

As far as I know they would rank the same SEO wise, but my SEO knowledge might be a little off. Also the last one seems to be easier and cleaner to implement on my end.

Please explain to me which is better and for what reasons.