I decided to use Blender to create my project because it's open source, which I like, and I hadn't ever used it before. I'd have to say learning how to use Blender was the biggest hurdle I had to overcome, because even though I have played around with 3dsmax and Bryce 3D before, Blender's interface was much different. Luckily for me, Blender3d.org provides copious amounts of documentation for Blender, and after a few hours of reading, I was able to start modelling the T-Rex.