htpc case advice

I'm looking to build my first htpc which will be Windows 7 based. I really like the look of the Antec MicroFusion Remote 350 but I'd like to go with 2 hard drives - one for OS and one for media. The larger one has a volume knob. Do people really usually want a volume knob? I've got a separate receiver so I'm really disappointed by how much not wanting a knob limits me. I don't suppose there is any other good use for the knobs?

My basic requirements are: not very tall (probably about 4" or less), multiple hard drives, clean looking front (but preferably I want it to look like a home theater component), no volume knob. IR would be nice but if I have to go with an external unit to get a case I like, I can live with that. I'm not sure about a vfd/lcd screen. I can't quite find info on what exactly I'd be able to see with one. Theoretically I like the idea of having one but not if it doesn't add real value. Can someone enlighten me about these, what particularly they will display in a Windows 7 environment?

Back to the hard drive issue with the Antec, do people commonly go with an external hard drive for their HTPC? Any particular disadvantage to doing that? What about SSD for the OS? Since I'm not that knowledgeable about SSD I'm not sure if they're all designed to go in drive bays or if there is some other form factor that would work with the Antec.

I'm thinking I'm going to have to go with the Antec Micro with an external hard drive. But I'd like to get input on these questions before I proceed. Thanks!