What's not to like? I got one and it's a fine unit. Like Bling said, he has a CZ20 and the 21 is the same unit, but with revised pinpoint button and there is a battery door gasket revision too. As far as salt water submersible discriminating detectors are concerned the Excal/Excal II and CZ20/21 series are the top 2 legends of all time. I will tell you why I like it.
1. The ground balancing is no big deal.
2. The unit can be run at almost 10 on Sens in Auto Tune (all-metal), with stability.
3. The unit can be set to boost 6 on volume, making deeper targets get louder in volume.
4. The unit has good discrimination, when used, but will need to be backed off on Sens, but not a great deal of loss on depth is seen.
5. The unit is more likely to bell-tone(overload) over a large target, saving me dig time.
6. The unit is VERY easy on batteries, consequently I had well over 30 and changed them out, even though it was not fully discharged yet.
7. The unit seems to have excellent stability and sensitivity.
8. There is probably more, but I need to think about it!
CZ21-10, on Anderson Straight Short Shaft and me, I like it!
[attachment 84378 CZ21.JPG]