I have the Dyson DC07 Animal-I'm sure you've heard the raves but I'll tell you why I like it and you can decide if they are important to you.
It has a long cord-not having to unplug and plug in cord all the time.
The hose for doing stairs is long-no balancing the vacuum on the stairs. **added**I also like the hose for cleaning above my kitchen cabinets
The suction is amazing-I have used other vacs on a hard floor and some dirt gets in the vac and some flys out the back-not with the Dyson.
Drawbacks for me-It has such good pick up power I have to clean the roller brush more than other vacs. But-my carpet feels new again when I use it.
I haven't really needed the extra attachments that came with my vac. I use the ones that came on the vacuum tho-the typical attachments that come on most vacuums.
The Dyson is heavier than the Oreck though.
HTH! Jen