i've had one for about 6 months.
it's not of the same quality as a really good machine, with really good beans, made by someone with some skill ... but it's actually pretty good for a completely hassle free coffee.
there really is NO mess, i use it as my only source of coffee - I had previously tried manual espresso machines, stove top espresso, and plunger -- but all were too much hassle to use every time at home, especially given that I have 6-8 cups per day!
it is still possible to make a crap coffee with nespresso - if you extract too much (put too much water through the pod) it will be bitter. The pods really are different - I like the 10/10 intensity varieties.