I’m looking to upgrade my Magnum Dynalab MD106T???

I'm using an MD ST-2 antenna which is installed outside. I've experimented with placement and find it works better on my back yard fence than on my house roof. The tuner sounds good but I just wonder what could be a nice improvement. I've  noticed that different tubes give different types of sound. I am currently using  Amperage tubes and they are nice. I may be missing a little sparkle which may be a result of total cable upgrades everywhere. I've been listening to the tuner all night long now giving my transport and streamer a rest. In all honesty my tuner sounds good now that warm and the reception is good this evening. I just ask about better out of curiosity but my current tuner is quite nice.

The Accuphase T-1200 is $7500. Is it that much nicer than my $4000 MD106T?  

I would look into getting a better antenna before replacing an already excellent tuner.

I doubt very much that the Accuphase would be better. Nowadays there are very few top quality FM broadcasts that would justify paying that much for a tuner. I use a Magnum MD90 with an attic mount yagi type antenna. Save your money, that tuner that you are using is top of the line!

Your “true differential” balanced output requirement will significantly limits your options.