The Mk1 was designed to be wired to the ignition. If you wire
it to the constant power, then it's up to you to deal with other
issues that will arise (amplifier pops, etc). That's what I had to do
when I wired my Mk1 to constant power.

Certainly.

I might just be lucky in that my (cheapass, currently looking for
something nicer) amps behave themselves.

/Michael