Kind of like audio equipment and speakers being where you "hear" the quality, the 2nd stage is generally more noticeable for performance than the 1st stage is, unless it's really not doing well.
Your video is kind of normal behavior, though as a balanced diaphragm I'd expect it to lock up a bit faster. It might (maybe) benefit from an overhaul if some parts are not well lubed.
Near as I can tell from the Cressi site the 2nd is a downstream compact. Well tuned it could do pretty well but maybe not as well as a good balanced, especially a larger face 2nd since that can have better leverage on the diaphragm. Reviews tout it as a dry, very light and comfortable 2nd. Seems the system is kind of marketed toward travelers.
Swap the 2nds between regs and see how that feels, even better if you do it on a dive and to A/B comparisons in dive conditions. Go to 60' and swim like hell for half a minute to push it. Shop testing only gets you so much.
(Note - make sure you have the venturi switch set right. I overhauled my SP 250, dove it comparing it to my SP 109 with a new downstream poppet and was dismayed at how poorly the 250 did. Then I discovered I had the venturi switch set wrong.
Set it right, it was fine again. I generally just leave them open so did not check it until I got out of the water and was trying to figure out what was wrong.)
