I have been a happy Compiz user in my Mint desktop. Sure it uses some resources, but as is true for many, my computer can handle this with little performance hit.
About 1 1/2 years ago, I began experimenting with another small use of resources, the various docks available to Linux which utilize Compiz's 3D offerings. I saw this as one more way to add a "wow" factor to show off Linux to others.
I settled pretty quickly on AWN (Avant Window Navigator). AWN seemed the most mature of all the docks available and I was a fairly happy user for a year. I really like their 3D turn effect for icons on its dock. During this whole period, I would notice some strange behavior; icons suddenly changing or disappearing from boot to boot. These tended to be my custom icons, either replacements for standard app icons, or for installed apps, especially my Bible app of choice, e-Sword (a windows app run through wine). Sometimes an empty space on the dock could still be clickable to start an application, but that was just weird!
This led to a second dock-go-round.
However, this time Cairo-Dock, showed much improvement over its previous version. Most of all, it is stable. Boringly (in a good way) never changing from day-to-day, unless I change it. That is what won me over, even more than its stability, was its wonderful, "control center" approach to configuring all its effects, from appearance (themes, backgrounds), behavior (such as, screen placement), and accessories (applets to replace your systray)
Give Cairo a place on your desktop...enjoy Functionality...and Flair!