Was about to suggest those, but you guys beat me to it.
Although I'd maybe recommend Shadowrun: Returns as well, since it's the first entry in the series. Not as good as DF and HK, but you get the general idea what the series is going to be about, plus the improvements (both gameplay and writing wise) will be much more noticeable and welcome with each subsequent game, IMHO.
Also, you can import the Returns campaign (Dead Man's Switch) to Dragonfall engine, so you get all the new improvements like flanking etc.