Personally, I'd take take the POD over the Mesa. Unless you're talking Road King or Triaxis, Mesa's seem too flubby in the low end for my tastes. especially for dowtuning. POD = tight tone generally, and much more versatile. Pair the POD up with the right speakers and power amp, and it'll sound terrific (if you tweak it right
)
You want a good tube amp that handles low tunings well? The Peavey Ultra Plus kills for it. Very tight, meaty tone, with lots of growl. My buddie has one, it it's a monster.
