Recommendation on power amp

newtoncr,

Where are you located?  Read up on Nuforce or Nuprime amps, especially with Bob Smith of TDSS' upgrades to them--factory authorized by the way.  I've taken mine to 5 different friend's systems and the result was the same in all.  It was the best each had hear their system by a good margin.  I happen to have the Nuforce Ref 9 V3 SE monos w/ TDSS level 3 upgrades.  They are phenomenal and carry the Nuforce house sound with a touch of warmth, but with the TDSS upgrades, it's like they are on steroids--everything is better and now more reliable too.  You could hear mine if you are in the Chicago area or will visit soon.

Bob

I highly recommend McIntosh amps and it fits your budget well.

Check out the YouTube video of the Blades with Audionet amplifiers. 
System was well reviewed

If you don’t have a dealer, call up PS Audio and try either their 250 stereo signature amp or their 300 monoblocks. I just bought their amp for my large Ushers. They have a 30 day trial period and they take tradeins. Highly rated. Also, why not drive the blades full range and adjust the subs to bond in properly? I did this and I know others do the same. Any of the amps you are looking at wil drive the blades full range.

I’d recommend checking out the Hegel H30.... plenty of power and hold on the speakers. KEF and Hegel play really well together