Last Z1's I saw proven were at Db Drag finals, when behind the HO Alternator van they had a stack of dead ones right out of the box //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif (including two that I dropped off and added to the pile)
I got two...mine are the 2nd generation...They did have some bugs in the first generation...that were worked out in these...there are bigger caps and more output than the first gen Z1's...The test on DD's website was output from the first generation Z1's
snoopdan proved the power of a warlord... search for his vids on roe of his tc 4hp. that amp is a beast, and is cheaper than the z1's. you could also get the warrior series, which is 3000 wrms @ 1 ohm.