Well having had shark, revo, bluefin, PDTuning and superchips on my car....................
I would say go with Shark. Their stage 1 map is far better than the Bluefin.
One thing that I will stress, is that if you go to stage 2+ with shark, go down to their HQ to get it done on their Rolling road and setup properly.
Out of all the above companies, bluefin was the one I wouldnt go back to.