QTR-Quadtone RIP

QTR has nearly 20 different paper settings in the "Type" box.  

Do these settings actually DO something different, or does every 
setting give identical output?  (if so, how about eliminating them to 
reduce confusion?).

Do they make a difference in setting the platen gap for different 
thickness papers, nozzle to paper distance, etc?

Up to now, I have used the "matte paper" setting for all my matte fine 
art papers, and "photo paper" for all my glossy, semi gloss and semi 
matte printing.  

Am I missing something here?

Thanks, Lou