The stock springs in the rear of the Speed 3 are too soft IMO, and under heavy braking from speed or those "oh crap" occasions where braking is required during a high speed corner the rear does get unsettled. Someone that has driven their Speed for some miles would be used to it and not let it get "sloppy" looking. I'm an experienced driver and know exactly where to put the car in the twisties, IMO it stays more stable and planted than my SVTF did, until you throw braking in there
Easy and cheap fix, no shortage of aftermarket springs and the available Mazdaspeed ones can be installed with stock dampers (bonus!).
Like macdaddyslomo said, the MS3 has a rep at the auto-x. I showed up for my first one and had all the local guru's asking for rides, lol.
04‘ SVTF/5, EAP, Pitch Black (rip)
# 908 of 1079, Born 03/16/2004
SVT SQUAD # 68
" I brake for saucy Pirate wenches"