I'm the only coffee drinker in our household so a Keurig is my perfect coffee maker. I just have the Keurig mini type, where you have to add water before each cup. That works fine for me, and it was the cheapest model, so I'm happy I bought that one. My biggest complaint is that K-cups can be crazy expensive compared to ground coffee. I try to use a My K-cup (which lets you use regular coffee grounds) for normal days and save my K-cups for special occasions and days where I'm feeling down.
Oh - I also love the variety you can offer guests with the K-cup packs. I like to buy different types of K-cups and then use all but two of them, and put two away for when guests come over. Then, when we have guests we have this huge selection of different types of coffee to pick from. People who don't have Keurigs at home always get really excited about choosing which one they want.