Having owned and been around all of the above...
I like the evo the best for a D/D. But only modded. If I had to take a STOCK car, and KEEP it stock, out of the 3? I'd take the STi 7 days a week. That 2.5l and all that torque, combined with DCCD... car is super fun right out of the box.
I like DSM's because they are like silly putty in my hands. I have fooled around with them enough that I can extract whatever I want from any of them... I know proven combinations of parts, turbo's I like, etc. I can do whatever I want and know how to get there. And they are by far the best looking of the 3. Evo's just do the same thing with seating for 4, parts cost more, and you get to start with a newer pile of parts.
Don't be so hard on the Subaru. In modded form they are the clear loser. But for all the more many people mod their cars... or maintain them... the STi isn't a bad car.