Minor Mod = New Market? What's the difference between an Audiophile and a ProAudio User? The Pro has a smaller disposable bank account but a smidge larger coefficient of physics training. And Pro livelyhoods depend on the gear we choose cuz we bang on 'em 14+ hours a day. AND we tell our Pro buddies when we've found something hot (the Model 200!). The Pro today needs a Mono Block with balanced Ins - preferably on pin2 Hot XLRs. [The Pro tomorrow will need digital Ins - preferably AES/EBU, but that's a different topic.] Studios since the '70s have either run balanced lines to the inputs of Amps (then terminated them to unbalanced at that point) or put "+4 to -20" boxes immediately ahead of the amps and dealt with the minor penalty of another transformer in the circuit. But with the proliferation of new "balanced power" systems (Equtek, etc.) the new trend is to balance everything for ultimate noise rejection. So if the 200 - or it's descendents - could suck in the hi-level balanced line, we'd buy lots of them. Same logic applies to the whole Outlaw Amp line...

seems like the new amp coming out is going to have balanced inputs, though it will be multichannel.

Humble suggestion - just buy a pro amp.

I believe Underwood Hi Fi will modify the M-200 to run fully balanced, although the mod is somewhat pricey.

If you're handy, you can easily add balanced inputs with this:

http://www.jensen-transformers.com/as/as012.pdf

Or you can use the Jensen PC-2XR. It's both an isolation transformer and an impedance matching transformer.