I know SZ and KTZ worked great for my rangers, but the banhammer is frequent and widespread. I'm on my third Ranger. I used SZ for the prior 2 and both of those accounts are bye bye. Now I'm trying out another injection bot (KTZ) and it's working great so far.
From my experience, injection bots (sz, ktz, mmoguider) are great for ranged classes more so than the pixel bots. The pixel bots tend to aggro mobs by walking by them, but the injection bots recognize all mobs and rarely aggro train if you set your ranges right.
For safety go with any bots other than sz and ktz. MMOguider hasn't been hit with the banhammer yet, but not to say nobody has been banned while using it. They just haven't been targetted by the GSU.
my 2 cents