Guild Wars 2

hows this build?
http://gw2skills.net/editor/en/?fgEQNAR8dlwzqq3UTmGaNJipCBHaBke0apWpVmBudhA

How would it do in different areas of the game? How to improve it.

Is a staff/GS build viable for PvE and WvW?
What stats are best for this build? Power and condition damage sure, is precision needed? or should I go for toughness/vitality to make myself last a bit longer?

Tips Please
Thanks in Advance