If you want your accounts to be "safe" and preventing bans, do ONLY use x10 def and x5 game speed. Anything else will just lead to get banned within a fay days, especially the currency cheat.
I know its really hard to not use the currency cheat but and its also hard to not overpower the character with godmode and atk cheat, but this will lead to high rankings and easy ban. The do not seem to have a detection mechanism but only take care of absurd rankings and statistics. I found out that game speed seems to be easy to set to x5 and increasing defense is fine too(but godmode will get you banned, probably mainly because you just survive too long on "endless" waves)