I prefer both Toad or SQL Developer. But I give more preference to Toad because of features like-
If you want to update your select result in toad, just add the ROWID
is your select statement. Once you select the records with ROWID then
you can edit/update your result grid.
Also, the session and Database monitoring monitoring features are much better in Toad. The only downside of Toad is that it requires Oracle SQL Client to be installed (which may be the case with any other non-Oracle branded tool), on the other hand Oracle SQL Client installation is not necessary for SQL Developer.