People think prime engram exploit will launch you to the stars. First of all, for every prime engram you pick, you will miss one day in the future, since the game detects it (doesn't matter if you don't pick, and they go to post master, once you "get it" and open it, you will have the cooldowns). Also, the best way to farm those, will have its limitations. Max object on the screen will prevent more than 3 or 4 Primes, before they start despawning, and you will lose primes, due to the fact PM will be full of blues. If you pick them up, then you lose the buff. It's cool if that was your last thing before the raid, knowing you will spend a few days without primes, but the biggest part of the grind is related to smart grinding (knowing which activities to do first, stop, grind blues, stop grind petra, etc), and A LOT of luck. Also, having multiple characters, taking advantage of the weapons to boost each character a little bit further by the end of the week. I've reached 540 pre raid with absolutely no exploits and just 1 character.