Polk Audio speakers are mediocre to poor designs at best. Couldn't find any data on your specific models above, but these from another thread (closed

) demonstrate exactly why:
Poor off axis performance (demonstrably audible) and a rising treble (also demonstrably audible). I suppose if you are older, with lots of HF hearing loss, younger but deafened by over exposure to high SPLs, or just plain like sizzling HF coloration (which is why you must take internet subjective tastes with a grain of salt...and realize how irrelevant they can be to what
you will hear/like), then something like those may fit your tastes.
It's possible to get good sound (measurable/verifiable via controlled tests) for your budget. The aforementioned Behringers are a nice choice, as are speakers available right here on the forum, which may closer match your original propositions:
Front towers $400 - free shipping!
Measured/reviewed here
Center $200 - free shipping.
Subwoofer $190 - free shipping.
Surrounds $80.
Total within your budget...and you can add a second sub later, or now if you feel like splurging.

Best 'o luck.
cheers,
AJ