Senseo gives a nice thick froth at the top of the coffee, which I find delightful, especially for breakfast. I make a large cup. Although the standard pods are fairly bland, there are Colombia "blend" and Brazil "blend" pods that are pretty good, and an authentic-tasting Sumatra "blend" but that origin is not to my taste. Amazon often has them at a good price.
During the rest of the day I use the Keurig. It gives a variety of excellent coffees; the Timothy's Colombian La Vereda is particularly good as is their Colombian Decaf. Green Mountain's Heifer Hope and their Nantucket Blend are nice, as is the Ghirardelli hot chocolate; for the rest of Green Mountain's K-cups I can take them or leave them. Again, Amazon has the best prices right now and if you are a member of Amazon Prime or order more than $25 worth, you get free shipping which brings the price down even further.
The adapter that lets you use your own ground coffee beans for the Keurig works particularly well; there are several third party ones for the Senseo; most are fussy and tend to be fragile thin plastic that replces the pods; one is quite sturdy and all-metal and replaces the pod holder, but it does not give froth--perhaps Philips has patented the very fine orifice on the standard pod holders that causes froth to form.
One cannot help but notice that most of the Senseo and other pods come from mass market roasters, while K-cups come from specialty coffee companies; that's probably why the coffee is so much better in K-cups. Even the mass market roasters' varietal pods (Colombia, Brazil, Sumatra) are "blends" with other coffees; I have found no varietal pods except for some micro-assemblers' very pricey hand-made ones.