Guild Wars 2

Can someone give their inputs on these following thief questions for new GW2 player..:)

a)

I have heard that unlike WoW a thief cannot be in stealth mode indefinitely.
Is this true ?
If this is true, can someone tell how long will I be able to stay in stealth mode ?

b)
I am leveling a thief and he is at level 4 ATM.
At what level will I get this stealth ability ?.

c)
Which spec/skills I should dump while leveling to create a playstyle of a thief similar to “Subtlety Rogue” of WoW ?.

For those unfamiliar with WoW, I am looking for skill/build where a thief creeps upon his target, unleashes heavy damage and escapes before he gets into serious trouble.
Because of this very “hit-n-run” nature, this type of rogue is comparatively squishier than others which I am okay with.

Hey vpy,
a)Thieves can sorta stay in stealth forever, but they have to trait and build towards it. This makes them extremely unefficient in any combat, but makes them very suitable scouts in WvW. If you are looking for a regular fighter build, you would have about a 10-60% uptime of stealth, depending on your build, with dagger/pistol panic strikes topping at 60%, if you take the shadow refuge utility skill).
b) The first stealth will most likely come from your dagger offhand weapon skill 5, just check when you unlock weapon skill slot 5 by hovering over the grey lock just left of your healthbar.
c) Look for a build called the panic strikes dagger pistol build. You will combine the pistol offhand 5 skill with leaping through your smokefield with a dagger 2 (heartseeker) this will give you practically unlimited access to stealth after doing heavy damage to the enemy. Here is a link to a commonly used dagger/pistol build: http://metabattle.com/wiki/Build:Thief_-_Dagger/Pistol
d) Have fun with your thief, I hope you like gw2 and stay with us!

-Mair

Check this vid to have some idea about how much stealth a thief can maintain.