Welcome 05king.
I'd start by giving us the specifics on the speakers, namely their model numbers. Hard to say if you should keep one or the other if we're not sure what you have. Just going out on a limb, I'd say that you may have a good starting point to build on with the Polk speakers...but again, that depends on what you have. Their subs leave a little to be desired when you compare what you pay for them to what you can get now, particularly with the online retailers (Hsu, SVS, etc). But who knows. Drop another post with the specific model #'s and let's go from there.
By they way, you definitely have a good start with the 3805. That's a solid receiver.