IMO, the EVO 400 is overkill with the Klipsch. The EVO 300 a much better choice. Half the power tubes at replacement time, more than enough power, etc..
I wanted to buy the 300 but chose a Rogue Cronos III instead (for Forte 4s).
The Rogue is a fantastic bargain (nice fit-and-finish, headphone jack, phono preamp, Triode switch) but it doesn't accommodate EL34 tubes. EL34s are the preferred tubes for low-to-mid power amps, for many people. The EVO 300 was $1500 more than the Rogue.