I'm talking the cold water system for the AL not the APEKS, take your time to read
As well I clarified that the they don't sell the Cold water kit for the Mikron, they do for the Titan, and that is what I did with my Titan's regulators.
DST, FSR, DS4 are all sealed system, overbalanced, so far I know it is the same regulator internals, the body changes, to better aid on hose routing depending how your dive gear system.
The reason, of why they become over-balanced is that now you have a little bigger area ( the second diaphragm ) pushing on your main diaphragm thru a rod or help to do so, this suppose to aid in the balancing, in for what I understood that is what they called overbalanced, with a balanced one wet system, the spring is doing the work alone, apparently that difference of contact with the spring over the diaphragm disc vs the dry.system that have a another diaphragm makes the difference.
That is why they say you go from balanced to over-balanced, it maybe just a name for marketing very possible, but it does make a difference, it did in my Titans
I guess we can ask directly the AL / APEKS To clarify that