i've played around with it a bit--though i haven't been able to actually, thoroughly playtest a whole adventure or anything. but this is pretty straightforward, and i feel, pretty weak for the equivalent of a 27th level item (according to MIC). so i'm dropping the base price to 200,000gp, which puts it at 25th level along with the +5 vorpal sword. i still feel that to be too expensive, but we all have to compromise somewhere, right?