I'm 260#, (300 in gear), and have the bike set up for LD touring with a 5 gal fuel cell, 1 gal water and full panniers, plus some more odds and ends. I've been running an 1100 lb spring for 60k miles or so. When the first shock got to 45k or so another forum member very generously offered me his low mile stock shock, so I swapped it over to the stiffer spring and that has about 50k miles on it now and is starting to get noticeably looser in the corners. I'll probably upgrade to custom suspension and have a real suspension shop set up the front end as well. Over due, but budget was too tight in the past.
Over all, the stiffer spring did what I needed it to do and the oem shock seemed to do fine handling it. 50k on an oem shock, I know it's sub-optimal by now.