Tried coffee via the Keurig K cup for the first time today while visiting a relative. She likes the convenience and speed of it. I tried it and was not impressed. The coffee seemed weak. To be fair I decided to experiment a little. I finished the first cup and tried a second (drinking it black instead of with milk and sugar as I did the first time). There were several types of K Cup coffees available to try so I did try both a flavored (Kahlua), a tea (spiced chai) and one of the new Starbucks K Cup brands. I am known to be a coffee drinker so did this with the blessings of my relative!
To me the pros of the K Cup are that the coffee is made fast, to order and is better than instant. The cons though are that it all tasted weak and flat. My preference is always for iced coffee (sweetened and with milk). None of the K Cup varieties stood up to that. Even using a little less water I could not get a cup of coffee that I was truly happy with.
A couple of weeks ago I mentioned getting a used percolator. I am still very pleased with it. I am not sure if it is supposed to but it makes crazy noises (bangs and burbling) while brewing. The coffee made from it stands up to iced! I even tried to brew a pot of tea with it and it turned out nice. A bit strong (I put in too much loose tea) but it stood up to being iced.
I think a K Cup would be good if you are in a place without access to a coffee maker (especially to avoid instant). Especially if someone prefers weaker coffee. I am not sure if it is because of the speed or the coffee itself. I know you can buy refillable filters to put your own coffee in a K Cup maker. My relative is planning to buy one. I am going to have to try that next to see if it is the coffee or the maker.