Usage is ~70% music, 30% games, with headphones sometimes. I have a pair of HD555s. Am getting the Essence for roughly 140$ US, with a 3-year warranty from Asus India.
I just got the Xonar DX (PCI-E short height card) two weeks ago and was just floored with the leap in audio quality when compared to onboard sound! I felt it was entirely worth every penny. Your Essence should be even better.
I am using the Essence on my HTPC for music playback and I can tell you that no card beats it for two channel music unless you go for a Lynx at 700$. It replaced an Auzentech X-Meridian and I felt it was a good upgrade for two channel music.
It also passes fine DTS Core 1,5mbs used in MKV movies through the optical out but it will not pass Blu-Ray sound as you might already know - for this I use a standalone player. For gaming I would not recommend it at all though.
For Essence money in Europe you're better of buying an external DAC if music is more important to you, even half decent ones like the Essence are poor cousins to a mid ranged DAC.
But you seem to be getting it alot cheaper than us so .....