We have had a lot of false alarms and sometimes where they haven't picked up motion when they should.  Also the battery life on these seems to be worse than a 2GIG motion.  Mainly though the Crorzar motions have a ball joint and swivel.  Although this makes it nice for initial aiming, anyone can simply bump or move the angle and it is no longer effective.  Too many time we see the motion pointing at the ceiling or when a customer changes the battery and puts it back on it is upside down.  This makes these motions too unreliable.