Yes that is the 600t. honestly I cant really be a judge of what "loud" is. I have 3 120mm fans (All quiet editions) and 200mm (Cool master, corsair doesn't make a 200, YET)fan going right now and its quiet to me but to someone else it could be kinda loud or too loud. I do think it is an upgrade from the 300. The build quality is nicer and the build materiel is better so the sound be quieter.
The mesh paneling on the top is great, it covers up these