I think the 606 is a great choice in your price range. It is more powerful, and it delivers much less distortion. I found it online at Amazon for $338 and free shipping (may be cheaper at the going out of business store). It also has TrueHD.

A great choice in your range.

Now, to upgrade your speakers, concentrate on the fronts first. If you are willing to wait and save a bit, get the M60s. I would not recommend any pair of speakers for the $262 you would have left in your budget.

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