Toad with the DBA module allows for regular DBA tasks just like OEM, ie, email/paging, exports/imports, tablespace map, tnsnames mgmt, etc. The ultimate difference is the cost. The PL/SQL editor is great and there are a lot of nice additions in Toad that OEM lacks and a much cleaner interface but does the cost justify this? It's up to you. I use Toad (sounds like an AA statement doesn't it?) but I use OEM once in a while because of the OMS side (I use it primarily with 9iAs r2). I prefer Toad but if cost is a major factor then you are fine going with OEM - just not as a nice an interface IMHO.