5/11/34 is probably November 5, 1934.

E. von Hoegh mentions using a lens hood, and I'll second that. Looked at my chromes and negs taken with that camera and yes, sharp - the lens is sharp. But I had excessive flare. Again, my specific camera had cleaning marks (imagine cleaning a lens with steel wool - I recall it was worst cleaning marks ever)...

It's very well engineered though, for example the focusing is done by four geared helical pillars. So if you get it cleaned - it should last forever.