I had the SHL5+ paired with a Parasound a21+ and they sounded excellent together, the smooth, punchy Parasound sound is a perfect match for the Harbeth.
The Parasound house sound is represented in their integrated amp, the HINT 6. At 240 watts / channel at 4 ohms you will not be lacking anything with the 5's.
Save some money over the other choices and enjoy the sound !