Atul,
in long term you can find duplicate content if you don't prevent it. (just because there might be some path problem).
For ex.
you have product A that can be reached through Cat. A or Cat. B, so you will have two paths:
example.com/catA/prodA
example.com/catB/prodA
Which will be the same product reached from two pages -> two different URls with same content -> duplicate content
Regarding Frames:
Currently you have 1 URL because of the frames.
If you would go for 1 page for each product, then you could optimize better the content for the specific keywords.
Istvan

