For gaming I'd suggest an Astro MixAmp down he line. Fantasic little device.
Ok, so i'll settle for the Sennheiser HD 598, even if i've noticed that they're slightly more expensive than i thought (175 euro, the 150 euro pricing was a limited offer i missed! :( ). Will i need an amplifier to connect these with my ps3? I was considering the Sonic Impact T-Amp 2 Gen because of the low price and enthusiastic reviews, but i read somewhere that it doesn't work wonders with headphones. Can anyone confirm this?