I agree w/the strummonster. I have been playing 7-string guitar for 1 year, and one of the big advantages is that you don't have too deal with drop D tunings, or tuning down a half step, everything is right there. I think it is really an amazing instument whose capabillities have not been explord yet.
I have been playing for 20yrs. & the 7-str, gtr. really made me excited to sit down & practice again. I highly recco. it.