Don't listen to the other reviewers who mention the PSX, this game was on the original playstation but not the PSX, the psx is an entirely different machine. The PSX is a Sony digital video recorder with a built in playstation 2. I remember playing a bit of DD back on the original PS but never got to finish it, since the playstation I was playing it on wasn't mine. Still if you're in the mood for some dungeon crawling this game is still good.
I first saw this game when it was only on kickstarter. I watched it make its debut and obtained my copy through another source only because I had it preordered. Although I fully plan to buy it here on GOG just for the DRM-free peace of mind, including the DLC. As for the gameplay I find that for me it plays best with my PS3 controller in hand and my gaming headset on. It's not quite what freespace was, but just as good, it reminds me more of a rogue squadron type of game than ace combat though. The most amazing moments for me come from the tight moments when you transform to take out a capitol ship just in time to save your own capitol ship from devastation. If you prefer space fight/flight sims over space strategy this is definitely one for your collection, as it doesn't disappoint; just remember that it isn't as in depth as Freespace.