I've got the opportunity to purchase a Mesa 18" and a GK 400RB for $325. What do you think? Go for it? I've got a Henry the 8x8, and figure the Mesa would give it that booming low end that it doesn't have. The 400rb...would that work well with this setup? I'm kind of leaning towards buying the whole setup, then selling he 400rb on ebay...for profit ;-) Any input is greatly appreciated!