Anyone experienced the Luxman MQ-300 or/and The Air Tight ATM-300R?

Thanks Charles, you are totally right about trying in your own set-up . What is really a surprise for me is that it is actually much more powerful than I thought. 

h_bomb,
I can understand your preference for the 300b compared to the KT 88 amp you currently have. The KT 88 is a very good sounding tube if well implemented. However IMO a well implemented 300b is quite formidable and alluring 😊. I was a happy owner of a KT 88/6550 push pull amplifier. Once I got my 300b SET thers was no going back. That was 10 years ago. I believe that you will enjoy your Luxman SET amplifier for many years.
Charles

There’s no replacement for displacement they say. The MQ-300 has transformers that weigh a ton in comparison. It’s a wonderfully beefy 8wpc. I know from experience. I had no doubt it would work in his situation. 
I’m so happy he is experiencing that awesome amp. 
Enjoy it in great health!

I actually think they are 2 superb superbs amplifiers and I might keep both. The 300 though has a built I had never seen before though. It is really a statement product. 

Thank you for your update and confirming my suspicions that the MQ-300 is one of the best out there.

Yes, the build quality is quite out of this world. Pictures do not do it any justice.