What you want determines what you need.
If you want all the ammonia and nitrites gone from the water, bacteria in the water coloum, as provided by these cycling additives, will do just that. A good idea if you've already added fish to an uncycled tank and levels are rising to toxic amounts.
If you want bacteria to get established on the rock, sand and other surfaces, you need to feed them ammonia and nitrite via the water coloum. Adding cycling additives will take away that food source and slow the growth of benificial bacteria on the surfaces, stagnating the true cycle.
If you are starting with nothing but dry rocks, and you want to boost the cycle, filling a bucket with the new rocks, topping with water and then adding a bottle of cycling additive and leaving it for a day or so, should create the start of a nice BB colony. then put the rocks into the tank.
Let 'what you want' deternine your actions. don't be fooled by test results.