The Modwright LS36.5 is very revealing. I use IsoAcoustic Orea footers and replaced the stock tubes with NOS 6h30s and a Mullard GZ34. I also use a High Fidelity Cables MC-1 Pro power conditioner on the outlet for the pre. I’ve found that many times a component that seems edgy is just revealing issues elsewhere in the system that need attention. All that said, The LS 36.5 works much better with the Modwright KWA99 amps than the M1200s.
As to the comparison with the BHK250, This is a post I made about that when I got the M1200s: https://forum.psaudio.com/t/can-a-bhk250-owner-be-happy-with-the-m1200s-my-review/26191