I wouldn't say it's easy, but it has a nice smooth learning curve. You figure out the basics really quickly, and the more advanced stuff gets progressively harder to grasp.
If you know Python, you might write scripts in Boo (one of the three languages that Unity has syntax for), but I've never even seen a single example written in Boo. You'll probably be using Javascript, which is fine, because every piece of javascript is pretty well documented, with lots of examples and stuff.
Using your own resources is really easy, just import them and then drag them into the scene. Rigging, animations, materials, textures, etc you set up in your 3d modeling program carry over into Unity. You can actually even use script to dynamically animate your character's skeleton, or specific parts of it.
So.. yeah, I'd totally recommend it. It's a high-quality easy to use engine for a fair price, with a shockingly helpful community.
EDIT: Videos of Unity games? Like the ones on my Youtube page, right? That's probably just my video recorder slowing down my already not-so-great computer. I've played good looking Unity games with 60+ fps framerates. There are lots of ways you can optimize a Unity project for faster loading and smoother gameplay. Unity even has a stats monitor that lets you see stuff like how many draw-calls you have in real time.