Let's say I buy the 'regular' iWatch model, but want a colorful sports band on it. Or buy a sports model, and want the regular band on it. And to complete this, buy a 'high end' model, and want a sports band on it, I can do this, correct? I'm only confirming because, personally, I want an iWatch, but want to be able to switch it out for every occasion. So like, if I dress up, I want to be able to have it look high class, but when I'm dressing down, not so much. I'm able to do this, correct? Or will I have to buy 3 different models?