i got rsd in 2001, and it was EXTREMELY mild until 2004 (it was also undiagnosed until last November!).
it's in my left foot, and from 2001-04 the only difference was i could no longer wear heels, flats, sneakers, etc. my pain was nonexistent as long as i wore good gym shoes with inserts. i also had to stop walking barefoot at that time.
in 2004 i began to have unprecedented pain flareups, where i had to go on crutches and get cortisone shots (which i've since discontinued). i also began to lose my ability to do weight-bearing exercises--over time i've lost running, all sports but water sports, biking, walking fast, elliptical, dancing, standing for extended periods of time.
but i'm still a "mild" case, as diagnosed by my doctor at the Rehab Institute of Chicago. i think in my case "mild" refers to the fact that my sleep isn't disrupted by pain, it hasn't spread beyond my foot, and the pain is usually mild to nonexistent when i'm off the foot.
yet it's still progressive, which is scary. i'm doing physical therapy, and tomorrow i'm being given a TENS box for home use. they think i could see some turnaround. i hope that's the case for both of us!