Like I said before, crankcase pressure = very bad. Unless you want to be spending a additional 15k after you buy it, then stay away from it.
They are giving you a line of shit if they are saying different valve covers will fix it. Either they are idiots or they are playing you for a fool.
If the catch can is filling in a simple test drive, then it is really really bad!
WOW!! Yeah filling up a catch can on a test drive! YIKES !! RUN!! my two catch cans fill up about 1/2" in them all summer.
Thats goona be a tear down to fix!!