Ditto on what others have said above
Any closed caseback model from Davidsen would be very hard to spot, since it would have a superlumed dial, upgraded crown and crown guard, fixed cannon pin, etc.
Avoid any datewindow model (I haven't seen one that has gotten it right. I don't know about the new 88 and other GMTs, but most suffer from wrong magnification, recessed datewheel, insufficiently bold date font, just for starters. I'm tempted to order the new 088 which is otherwise nice, but I can't imagine that the datewheel is not recessed given the GMT modification).
Date window is an instant tell, and all hand wind movements with a crystal back reveal one or more of the following: poorly proportioned OFFICINE PANERAI engraved fonts, wrong shock protection, errors in finishing/fine engraving, wrong swan neck, etc... These are very difficult to address, much less ask for out of the box. You can get lucky for a few but not all without much aftermarket effort.
Dials, sausage (raised number / dial markings) and sandwich (recessed number/dial markings between two dial plates) have varying defects and almost all out of the box reps suffer from varying degrees of bad fonts, poor lume, poor spacing of various elements. Davidsen's latest sandwich dials are very good in these regards, easily obtained and reasonably priced, and a more cost effective solution than little hero's dials which are reportedly near perfect, but cost (without lume, and bottom dials) as much to acquire as the complete "swiss" 177H that I bought last year.
Boy you probably weren't interested in all this, but it's an inevitability once you take the "plunge". Enjoy!