I've used Quest's Spotlight (I think it's similar to Foglight) and really liked it. It had a few bugs, but did well for monitoring performance. The historical graphs came it very handy when the business folks said.."We had a performance problem 30 minutes ago". It doesn't have the admin features though (I'm not sure about Foglight). So we used DBArtisan's Embarcedaro for Admin.

At my new shop, we have neither, so I use OEM. It's okay, but doesn't have everything I would like. It's charts only go back 15 minutes unless you are recording, can't sort Indexes by Tablespace, can't select multiple tables to truncate, etc. (I've only used OEM for a couple months, so I may be missing some things with it though)

Just my 2 cents...

Jodie