Assuming the produce does what it says it does, you still need to cycle the tank... or more appropriately, you will need to cycle your filter.
The product will immediately get beneficial bacteria into your tank. But that's just getting the bacteria into the water column. The moment you do a partial water change, you're going to lose some of that bacteria.
But when you cycle a tank, what you're doing is establishing a concentrated colony of beneficial bacteria in your filter. So as you change the water or other changes to your tank, you always have the beneficial bacteria in the filter.
And if you do use this product, you still need a test kit so that you can watch if ammonia and nitrite levels are getting too high requiring more product to use.
My suggestion would be to get your tank and filter, get some pure ammonia (no soaps or other additives, try Piggily Wiggly or Ace Hardware store brands), and get a test kit and start doing a fishless cycle. If you want to hurry things along, you could get this product to help seed your tank with the beneficial bacteria. But I still to the fishless cycle.