I've brewed several batches with only the plastic buckets, a 6.5 gallon fermenter and a bottling bucket. They work very well, they have handles to carry them, they don't break if they slip and bump something. It's a cheap way to get started and as you become more proficient and want to add things, you won't have a lot of money into extra things you won't need.
The buckets are plastic and can become scratched, but they are inexpensive to replace if that should happen to yours. I added a plastic carboy so I could have a secondary to add fruit or to free up a primary for more time to clarify a light colored ale. Then I added a second fermenter bucket so I could have 2 brews going at the same time.
I dislike the idea of a glass carboy. They are heavy, brittle, and slippery to handle. On the plus side, you can see through them to indicate what is going on during the ferment. I never have worried about the ferment though.