So I am a Dead Space vet. With that said, would it be unwise to start the game on Impossible? Impossible mode in DS wasn't that bad. However, that was after I finished the game at least 2-3 times. Zealot mode on DS2 is personally the way I enjoy to play the game.
I would say to start on Hard. I cleared DS2 on Zealot and I can tell you that enemies in this game are much faster and more agressive than their DS2 and 1 counterparts (and they typically show up in larger quantities right from the get go). You may want to do like I did and start on Hard to get a good feel for the small changes and then do a Zealot or Impossible run once you've got your bearings in place.
PSN ID: gmsephiroth gamertag: gmxsephiroth Currently playing: http://backloggery.com/gmsephiroth
Its funny this mode is called impossible, I am on chapter 7 at the moment and have run out of ammo and med kits once. I have plenty of different weapon options and quite a few rig upgrades already. Dead Space has always rained resources; but it is even more pronounced in this game.
The enemies are fast, aggressive, hit pretty hard and are bullet sponges but once you get a few good weapons you will be fine. I have noticed that on impossible set piece moments the obstacles always seem to one shot you as opposed to hard where it seems like you can take at least one hit from debris, mine, etc.
So far so good and I would suggest to anyone who is a dead space vet to start the game this way.