In EVO 1.01 or greater, Each turret takes up a gun slot AND a turret slot. So, if your lazira has 3 guns, you may still have 3 turret spots, but you cannot use a turret, as you have no gun slots handy.
The same holds true if you have 3 turrets. Since the turrets take up a gun slot AND a turret slot, you have no gun slots left.
This change also prevents any sane, non-cheating purist from buying a Zidara, as it comes with, what, 3 turret slots, 3 gun slots, 2 turrets, and 2 beams? Due to the turrets, you only have one gun slot left, but you have 2 guns (the beams). You have 2 beams already, so you can only hold 1 turret. And you cannot remove beams. So, really, you start off w/more guns than you should have, and, by the time you qualify for a Zidara, you should have some enemies. 2 turrets and two quickly drained beams aren't a very good aresenal. Hmm....Maybe I should release a quick plug that gives each Zidara 5 gun slots, or at least 4. Hmm......
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To each his own,
U-99