I would not invest in Silo. It is basically dead (i.e. has not really been in development for a long, long time). Instead, despite how "heavy" it is to learn, get Blender for free. There are plenty of tutorials out there (that are also free) and so you can learn the program. It is also full-featured, so you will be able to model, UV map, render and animate ... all for free. Modeling is tough, no matter which 3D program you use (free or otherwise). It takes work to get it down and it takes even more work to create models for real-time 3D games.