I started a thread here last week which touched on keeping the signal
chain the same to retain consistency in the sound of the vocals.
There were some here who were of the opinion that the key to a
consistent sound has nothing to do with gear, and that one should
always use different gear depending upon venue. Although everyone has
their own opinions, thought I'd post something I just read regarding
that exact topic.

This is an excerpt from a Mix magazine interview with Michael Pollack
and Derek Van Ord about mixing the Ben Harper/Jack Johnson tour:

"While Van Ord stresses that mixing monitors for Harper and Johnson
was challenging, it was alleviated somewhat in the fact that Harper
owns most of the rig. "Michael and I got Ben on that early," reveals
Van Ord, "because when we first started touring with him, Ben wanted a
very consistent sound, and to do that, you have to have the same gear.
So we pushed Ben to start small: buy your vocal microphone and then
you have to buy a certain processor."

Just a few other people who believe consistency begins with
consistency in the signal chain.