The main differences are that the Escape 3 has a steel fork, the 2 has an aluminum fork, and the 1 comes with a carbon fork and carbon seatpost. Otherwise, none of the components on any of them are exciting. Your goal, on any of them, would be to swap everything to Shimano 105 level components (need the hybrid versions, flatbar, for brake and shifter).

105 level components, if you bought them on your own, are about $450 by themselves.