Plz explain difference between the software systems for corporate finance

I want to set myself up to transition into a F500 sometime. How do these relateto/compete with/supplement each other?

  1. Hyperion

  2. SAP

  3. GP - Great Plains


At the moment, I work at a mid-size company and only the accounting department uses Great Plains. Us finance guys don’t use it (much). Depending on your responses, I might learn Great Plains to create a safety net.