I personally drink Decaf Sumatra for its full body and low acidity, but Colombia is less expensive -- and while not everyone likes Sumatra, Colombia is a general crowd pleaser. We either roast it barely into the 2nd cracks, or else roast it a good 30-40 seconds into the second cracks.
Note that this was decaffeinated in Germany using Methylene Chloride (MC) which is a pretty nasty chemical (it's a handy paint remover). It has a chemical reaction with the caffeine which dissolves the caffeine, leaving the flavor profile and body of the coffee intact. Normally you wouldn't touch anything that fell into your can of paint remover, but truthfully, there is only a trace of it on the coffee when it's imported (less than one part per million or... .000001%), and remember that MC is flammable --- it vaporizes and incinerates at 200 degrees, meaning that if you're roasting beyond 400 degrees, there's not even that slight trace remaining in your brewed coffee. And tests have verified this to be the case, which is why I'm comfortable selling it as a lower-price point option for a decent decaf vs the prices that water-processed decafs command.