as long as you take good care of them, there is nothing bad about it!
I went to the store to trade in two bearded dragons, and I also ended up with a 18x18x18 vivarium and 3 FBT's. Within 2 weeks I changed the setup and I added real plants instead of the plastic ones. I also am reading as much as I can find about FBT.
Have fun with your FBT's because they are funny animals. I have one that poses for the camera, and one that jumps on my arm. The third one is a bit shy.