Hi Eugen,
So you have 2 shooters and 2 collectibles? Sounds good
I see my collectible more as an investment only because I really will not shoot this gun. (It's also the first Luger I had ever seen as well as the first Luger I have ever owned... so that makes it more special.)
If I REALLY NEED the $ farther down the road, I would perhaps sell it, but I would look for a buyer who appreciates it as the collectible that it is. Otherwise it will go to one of my children... I don't know right now. For sure it is special to have.....(Had to sell my Winchester Model 94 when I first came to the Netherlands... that was difficult.) Perhaps I will build a collection starting with this 1917 DWM. Fascinating guns these Lugers. Brilliant design

Too bad the Mitchells didn't really take off.
In the meantime, I'm reading up on these firearms, shooting my P38 and waiting for my shooter 1918 DWM.