The Antec Three Hundred doesn't look like a "gaming rig" to me. It looks like a very simple (basic) black steel case.
At $55 it seems like an excellent choice for a basic system.
You nailed it. The 300 is cheap and simple yet offers all the features you need in a simple design and compact size. It's an excellent case if you don't want to break benchmarking records and/or don't want a mini-disco standing on your desk. I like it a lot for lower end PC's.