If you use a filter insert from a mature tank, the cycling process will only take about a week. I have used both the pure ammonia and decaying shrimp techniques--they're about the same as far as effectiveness and both have pros and cons. The good part about pure ammonia is that it starts working immediately, you can work out an exact measurement to add depending on your results so it's harder to overdose. The bad part is that it's more involved than the shrimp technique--you have to keep adding the ammonia as it is consumed. I have used the shrimp method to cycle a tank while I was on vacation, and it worked really well because it's more hands-off than the pure ammonia technique, I didn't actually have to be there in order for my bacteria to have a ready supply of ammonia. The drawback of the shrimp technique is that it can be messy--after all, there's a big chunk of nasty rotting sea food in there, lol. It also doesn't go to work immediately--the shrimp has to begin to decay before it releases ammonia.
You should test frequently no matter which method you choose. The reproduction of the bacteria depends on aeration and temperature as well as the availability of food--so add extra aeration and jack the temp up to around 82.