Best tube integrated with Merlin TSM-MMI?

Not tube, but the Luxman and Sugden Class A amps will run these infamously.

Never heard of ARS Sonum Filarmonia?
You can do a search on it here :)

I would consider the Berning ZH270 as good as it gets, if you have only two sources.
I have since moved to the ZH230 with a Berning ZOTL Pre.
It works well.
e

Class A amps may run them famously, this maybe true. Class A might help with the slightly nasal upper midrange I heard when I had them. I doubt you really meant infamously which means having a very bad reputation. I have heard them with the Berning ZH270 and agree with Egidius it is a fantastic combination. The Ars is good but not great in comparison.

Anybody tried the Eastern Electric M88 with the Merlins?