I've also used both. I like buckets cuz they are cheap and stackable. I like carboy cuz it's fun to watch the fermentation.
Pros:
Buckets- easier to clean, take up less space, not fragile.
Carboys- last longer (buckets will stain after a while... bust really cheap), look nicer
Cons:
Buckets- stain, and need replaced after a while.
Carboys- harder to clean, can break, harder to handle at times
Overall, I use buckets now, but would not hesitate to use a carboy if I had one at hand... I've heard they are better for long-term conditioning