I have a HH. I am a former Inspo dirver.
I do like the HH electronics, but there are a few things I dont like:

The HH does not have an ability to calibrate on anything other than 100% O2. Normally this is not a problem, but once you go Truk or Palau they usually have between 90 and 95%. The HH will not calibrate, will not accept when the cell get less than about 45 Milivolts (not sure of the exact number). When calibrating, the unit assumes you have 100% and that is the only option.


You do have to maintain setpoints on both handset in order for the deco to be accurate. I just leave the secondary on high setpoint.

The scrubber is big and heavy, and is aluminum. Although it has an electrostatic coating, it is subject to scratches, gouges, and reacts badly when in intimate contact with Sorb. Should have been made of delrin.

The ADV is not agressive enough. It does not supply air as quickly as I wish it would.

The hose routings could have been thought through a little more. I cut apart the back of CL cordura to streamline the hose routings. Alot better now, but I had to do some surgery.


The metal sub tank mounts need to have a lock out for the button. I had a dive boat rack press in the button and release the tank. On another dive, the dive boat rack hit the button and the tank fell out of the mount when I jumped in.

One of the metal sub mounts need to be reversed. They need to be mirror images of each other, are identical instead.


With all this said, I still am very happy with my Hammerhead. If I could change just one thing, I wish it were lighter / pack smaller.
The unit is solid, robust, can take a beating, and can be relied upon. For me, it is a perfect Rebreather for my use and I would buy it again.

Terry