Sukant

Its worth a shot, I've used Arctic Silver 5 in the past and I find NT-H1 to give lower temps. 

I personally use Noctua NT-H1 now after switching from Arctic Silver 5. Thermal Grizzly's Kryonaut is suppose to be very good as well but I find it to be too expensive for the amount you get. Also MX-4 is another paste that users will suggest as well. 

Yeah it is (speaking from reading about it, no personal use due to its price). 
 
NT-H1 works pretty good in my computers that I have used them in so far. I picked up my tube from Amazon, a 10g tube for $13 at the time which was better in costs vs the 3.5g tube.