Haven't had a chance to test the new seat suspension and Flex Forks until today, too wet. I can report a much nicer ride with those two items added, but although I installed them together I can say the seat suspension from Seatwarehouse.com is the most noticeable improvement. I had to readjust my deck after running the FFs for about 45 min., but not much. I'm running 3" front, 2 5/8" rear on deck height, which should be about right for St. Augustine and about where I had it on my old Craftsman.
Had a minor set-back early on today. Right after cranking the mower, getting off, then sitting back down rather firmly the engine quit. I suspected the seat switch connector had come loose since it was immediately after sitting down, but electrical power was out throughout. Checked the 15A fuse on the battery and it was blown, so I think the switch extension cable connectors touched the frame when I sat down. After adding the extension cable when installing the seat suspension there was some exposure at the connector so I added some insulation, re-routed the cable, and wire-tied it to the seat frame. Had no more trouble with it today and I think that issue is solved.