MIDI Controllers - TMD40

I am learning about MIDI controlling and have a few questions. I recently purchased a Tubemeister Deluxe 40 (TMD40) after catastrophic board failures on my Peavey JSX combo. I managed effects via stomp boxes before but am looking to get into the world of MIDI since the TMD40 has this capability. I have a 2-part question:

1) Based on on-line research I get the understanding that pretty much any controller will work with any MIDI controllable device. Is that true with the TMD40? Am I required to buy the H&K FSM432 MKIII, or will any MIDI controller work?

2) If any controller will work, is it worth the extra time that may be required to program the different channels? I have read it can be difficult to merge different brands with different numbers of banks, controllers, etc.

Does anyone have experience with the MIDI control of the TMD40 they would like to share (tips, tricks, etc.)? Are there any other pieces of equipment that will make my MIDI controlling experience more positive (effects loops, etc.)?

My $.02 - I suggest looking into using something like the Line 6 HD500X (or Helix if you have the money) and research "4 Cable Method". With this setup you'd have one box on the floor (the HD) doing all the effects and midi control of your versatile light-weight tube amp (TMD40).

Hit one switch on the HD, have your screaming lead. Hit another switch, have Sultan's of Swing rhythm. Modeling with tubes...