Both tools work well and allow generation of scripts. Toad is, by no means, inadequate.
ER/studio is a full modeling tool and the side-by-side comparison is superior, as are the options to sync logical-physical and physical-physical and then apply the changes realtime. Toad requires either running the whole sync script, or selecting individual pieces to generate script for, or selecting the pieces from the whole script once it is generated.
Toad will get the job done, and probably faster if you don't already have a model.