Going by their website the stealth really just looks like a longer standard Gen4, ie 300mm compared to 200mm. The standard gen4 only has 80mm forward of the barrel and I think that is the problem with it's poorer noise reduction, there is only so much space in a can with a liner over the barrel.
I'm guessing but I would only expect the stealth it to have about the same suppression as the DPT modular for twice the weight, same extention of the barrel and more cost.
I know my friend wasn't very happy when we compared my DPT with his standard Gen4.
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