I've "experimented" through an almost complete play-through using various cheats on the trainer. It is risky and you could always get banned obviously... but so FAR I've not had any problems. Everything from 300k + souls on a level 20ish ashen to setting lucky to 99, strength to 50+, dex, etc. with no obvious backlash. I'm probably looking at at least 30 hours of time (including afk time to see if it would get caught and destroying invading players with a dried finger buff active for hours for back to back invasions) As always use at your own risk... but *knock on wood* I've yet to notice any type of retaliatory action(s) or bans.....
I just hope I didn't curse myself by posting this...