I just wanted to get some thoughts off my chest  while they were fresh in my mind.  I bought the PC version of Dead Space from Steam (I couldn't resist at £5.10).  Upon starting it up for the first time, the following things were on by default.  Vertical Sync and maximum brightness.  For those that don't know, Dead Space uses shadow and dark corners to good effect to establish atmosphere.  The brightness issue severely affected this, I didnt realise what the problem was straight away as I couldn't put my finger on it, but after a couple of hours of play, I finaly realised and corrected the error.  Amusingly, adjusting the game's brightness to its minimum garnered the perfect look.  Another thing that struck me was how unbelievably "floaty" the mouse cursor was on the menu screen, (barely moving the mouse would move the pointer almost off the screen) before I had even started the game.  I erroneously dismissed this problem at first, as I was playing it with a 360 controller.  So there I was, playing right up until chapter 5.  I hit a brick wall, I simply could not get past the boss encounter in this area.  I was very low on health and ammo and had no nodes and almost no credits.  Being fed up of hitting this wall, I googled for some help to defeat it.  I stumbled upon a post that detailed the "floaty mouse" problem and explained that V-Sync was to blame.  Turning off V-Sync completely solved the problem.  I was suddenly playing a much more repsonsive game that was no longer "floaty".  A game I feel I would've enjoyed more and progressed through more efficiently (and probably would'nt have hit that wall), if this problem hadn't occurred.  What puzzles me is why this degradation in performance was allowed to happen.  If you coudn't solve the v-sync problem developers, why have it on by default?
 
These issues could have easily been avoided by merely having different default settings.  But instead my experience of the game has been marred.  I decided to restart the game from scratch.  I am currently in chapter 1 and have more health and ammo than I know what to do with (this didn't happen first time round).  Thanks a lot E.A., while I may well complete it, I seriously doubt I will bother with the sequel, if this is how you sloppily implement a PC game.