I checked the Pescasub reference out and the "Vintair" has a new plastic piston, not surprising as the older "Magnum" had an all-metal piston body. The new orange rear cap holds on with four small screws and does not screw in as it did before with the slimmer disc version used in the previous plastic rear cap. You would not want to lose those small screws!
There are two transfer ports, but if you look closely each has a molded strut running through it which interferes with the flow, so there are really four small holes, two on each side, exactly the same as it is on the "Magnum". Air flow may be improved, but maybe not a lot in it, plus after a "low power" shot the power regulator cannot easily be moved due to the pressure differential then existing between the inner barrel and main tank, so you need to reload the gun to subsequently switch to "high power". That is a consequence of the upstream valve system, unlike the commonly used downstream valve system where internal gun pressure always blows the plug out of the transfer port, the pressure differential existing after a "low power" shot in the upstream valve system clamps the valve shut, resisting your efforts to open it. All you need to do is load the gun or put some more air into it with the hand pump to remove the pressure differential, then you can move the power regulator again. To avoid this happening you just need to make the last shot of the day at "full power", that equalizes pressure in the gun's two chambers. Something that "Vintair" owners should bear in mind as that gun will work in exactly the same way as the "Magnum" did, the mysterious "jamming" of the power regulator knob had me mystified at first until I figured out what was happening and is nothing to worry about.
The new muzzle looks to be the big improvement as the relief ports are much larger and there are two steps in the muzzle nose allowing different size stop rings or washers for the use of either 7 mm or 8 mm diameter shafts. I still use a "Magnum 95", it is black as the ace of spades except for the white trigger and safety slide, so the orange parts on the "Vintair" may improve the visibility of the loaded gun if it is dropped (in depths where orange is still visible), while the power regulator "Vintair Plus" gun has a grey handle replacing the black handle on the single power "Vintair" gun. I assume "Vintair" is derived from the words "Vintage Air".
The Scubapro "Magnum" was intended to be a better quality gun than the Mares "Sten" it was then based on, so it was and is a good quality gun and great to see it available again under the Salvimar brand. Scubapro dropped the line when they quit the spearfishing scene, concentrating on their scuba diving customers instead. I expect that most parts will be interchangeable, except for that rear cap, although the old cap may screw into the pump threads on the new gun if you don't like the new cap.
