Got the Dead Space 2 platinum trophy today - and it's actually my birthday too! =P
Now for a Hardcore Mode report...
My 3 saves were:
1. Chapter 7 - before the solar array.
2. Chapter 13 - right after the giant drill sequence.
3. Chapter 13 - right before the eye surgery.
Died 5 times (arranged in death order):
1. Chapter 3 - Breakable glass part with Exploder. I didn't break the glass, but I shot the Exploder and died. The explosion distance is pretty far - I seriously thought I was safe.
2. Chapter 1 - One shotted by the first Puker encounter. Without any armour they one-shot you at close distance.
3. Chapter 2 - The first time that the Exploders appear. I sorta just tested it out again, shooting the Exploder at a fair distance (but still not far enough), and died again.
(So after learning that you really need some serious distance from the Exploders, I advanced carefully and made it to Chapter 7. Was gonna save after the solar array, but getting kinda shaky after staying alive for so long, so I thought I'd play it safe and make my first save just before.)
4. Chapter 14 - Got into an awkward position between the Hunter and another Necromorph, and got hit real hard by the Hunter and died.
5. Chapter 14 - Died at the eye surgery.
(I was attempting to make my last save just before the last boss, since my second save is already at Chapter 13. But after those deaths I got sick of playing that section again, so just made my last save just before the eye surgery.)
I just used the Plasma Cutter and the Force Gun the whole game. The deaths made me waste around 5 hours.
And I attempted Hardcore just after my Casual difficulty playthrough, so I breezed through Zealot mode with the Hand Cannon in just 3-4 hours.
All in all a great game! Don't really care about multiplayer though - PSN is down anyways.
Oh, and if you actually stay to the end of the credits there's some radio dialogue there that hints a further sequel!