eds111

I agree it is the seal that would let the moisture in. A hard shell case with the latches closed forms a pretty tight seal. I would at least store the guitar in the hard shell case in the winter. I always have hydrometers inside and outside the case, but I admit I am fairly obsessed with humidity...

It's just cosmetic. There is also neck binding, a different pick guard and a different rosette.

My L-48 wasn't too loud either; sounded cool though.

Yes, look for an ink stamp, mine was below one of the F holes. It was very faint, interesting subject. I had an L-48 and I gave it to my nephew. I always wondered when it was made. I guessed early 50's.