I've had this guy for about a 18 months and it is one of my favorites. It is slower than the HP Prime and the TI-nspire CX II CAS, but still blows the TI-89 Titanium out of the water as far as speed goes. The huge touchscreen gives it a unique UI that is easier to navigate than the TIs. I've found that this is the best of my collection for linear algebra, and it is the easiest of my CAS calculators to use.
What's the pen? That looks gorgeous!
It's a Hongdian 1851 Forest Rainbow extra fine inked with Diamine Emerald. It's even prettier in person!