What power amp or integrated amp are you using with your Harbeth speakers

The problem with HUG is that AS clamps down on anyone giving a subjective report on the sound of a amp+speaker combination.  AS uses Hegel because they fulfil all his requirements/criteria for good electrical engineering, not because he favors their sound signature.

The point is that there are a number of pre-existing threads here and elsewhere that report good results with a strikingly wide range of amps, both tube and SS, and both modestly and high powered.

The Harbeth importer in the US has shown them paired with Luxman and Vinnie Rossi, among others.  Two major Harbeth dealers demo them with LFD and with high-powered tube Conrad-Johnson.

Bottom line: there is no unanimity.

This is the guy who has his 40.2's in a small room.
https://www.whatsbestforum.com/threads/benchmark-ahb2-amplifier.25366/ 
He's using bridged Benchmarks.  380W should do the trick!