Reply to my question to my #1 supplier of Walther kit : Ref: Exchange LG400 regulator, for the standard 16J LG300 Regulator (?) " Hello, I just got of the phone with the export manager from Walther and he couldn't tell me for sure but he thought that it might be possible. He's gonna ask his technicians and he will get back to me tomorrow. We are actually the only gun dealer in the world I think who already has all the available models of the LP400 and the LG400 on display and I can tell you, these guns are absolutely stunning. Unfortunately we are not allowed to sell them until january." ...I wonder why I also requested they take some real close up pics, and photos of the actual gun from all angles in their shop... Will keep you posted as soon as I get updated info & pics.