I had 4A SAN-SMF the other day - very nice. 6C/D were empty and looked very spacious as I glanced over. Great service, too. I connected to UA SMF-DEN on a miserable 737-900 and it hardly seemed like F. Seat 5A is the pits: missing window, limited recline, less pitch than AS and a whooshing toilet right behind. Plus United's finest "service."