In the amount of time you have to cycle the tank, all you really need to cycle it is one decent piece of live rock to introduce the bacteria...and then you need to do what you can to encourage it to keep multiplying.
IMO I would avoid the additives as they are primarily nitrifying bacterias, and unless you already have a source of ammonia, you will just end up with a ton of nitrate (for your rocks and sand to adsorb) and throw things out of whack.
Do the raw shrimp thing to raise the ammonia level (unless you have plenty of dead crap in the current rocks).
DO remember that you need to feed the bacteria as it is multiplying! The bacterias that you want to encourage do need to eat! A pinch of flake food every few days will do that for you
I would also be sure to be running GFO and carbon already to pull more nonsense out of the rock you have in the tank. Doing so will not inhibit the bacterial growth.