Hi, have you considered a Wyred4Sound 250 watt integrated amp. I love mine, I have speakers with 15inch woofers, and I think netflix is doing structural damage to my house. The amp is dynamic, powerful and pretty smooth, but not dull. Plus seems to be pretty resilient to loads, its like 460 watts at 4 ohms with excellent protection circuitry. Worth a look I would think, same price range as krell s300i. I see that some talked about Peachtree 300 that is very close, both use ICE amps. I have never heard the Krell s300 but do read reviews, it might not be right for Klipsch horns.
Good luck!
Good luck!