What are the differences btwn the various versions of this amp? Do they all have QSK as a std. feature? Vacuum o/p relay in all models? Dahl xmfrs? Lane Ku7i -- FAQ on WWW: http://www.contesting.com/ampfaq.html Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com Search: http://www.contesting.com/km9p/search.htm