Interivew?

I had an interview today that lasted roughly 3 minutes. I was then told that I made to the second interview stage and had an interview scheduled for tomorrow. Sounds ace, doesn't it? I actually received a phonecall one hour after emailing my application to this company, so I was rather suspicious before I even got there - since when do you get offered an interview that quickly after submitting an application? The interview itself wasn't terribly indepth. They asked if I was motivated, ambitious etc. and I simply said 'yes' with no further explanations required! Also, a couple of the other candidates got a second interview and I thought it odd considering some of them had turned up in old jeans, trainers and a t-shirt - hardly management material. I don't mean to sound harsh or judgemental, but in business that attitide to an interview doesn't wash, it certainly shouldn't get you a second interview! I love the alternative/gothic look, but I sure as hell wouldn't wear it an interview if I wanted to be taken seriously.
This job (which incidently is with a 'recession-proof' company) is 100% commission based with very strange hours for sales (12:00 to 21:15 Monday to Friday and 10:30 to 17:30 on Saturdays). Apparently this is train you up to managerial material in record-time. 8 months, in fact. Hmm. Add into this it's a self-employed position and all-in-all it seems far too dodgy. Maybe I am being cynical, but I have turned down this second interview as I can't shift the feeling that something just isn't right about it.