Either if its short haul or long haul, I'd take 17.2" width & 32" pitch over 17.5" width & 31" pitch any day. The difference in width is marginal & the extra inch in pitch might allow you to cross legs (For me the ability to do this makes Y flights much more comfortable).
I would prefer 19" width/31" pitch over 17.2"/32". If you calculate 17.2 x 9 / 8 you get to 19.3"....