Not sure if this pens are matching to the topic but here comes my Mercedes!
The first pen is a safety pen. Unfortunately, I am not able to restore this filling system, and the pen lives in one of my drawers...
I also have a Mercedes. I reckon mine is from the fifties. It sports a broad oblique gold nib and I would say its quality is at least as good as any second or third tier Montblanc of the period. In fact, by contrast with my Montblanc pens of the 1940s and 1950s, the Mercedes has the cork intact and takes ink perfectly after more than 50 years.
Cheers
Carlos