I tested cycle in two 10 gallon tanks, which I was using for 1. a quarantine tank and 2. a hospital tank. Added 10 pounds of aragonite (sp?) 10 pounds of uncured lr from the same shipment, identical filters, identical heaters, and identical starting perameters. the one with cycle was at 0/0/20 in 27 days, the tank without it took 43 days to reach the same parameters. Personally I did not find the 8 dollars for the bottle excessive, and my test results seem to demonstrate that it does have an effect on tank cycling, 16 days in fact. I have also used it in my main tank without any adverse results.
I agree that this is not a hobby that should be rushed, and even after you have good parameters you should still wait, but unless you have honestly given something a shot and have reasonable results from it to say it did not work, I would have a hard time agreeing with making the automatic assumption that it a waste of time and money. A number of things could have killed $300.00 worth of fish, or caused a cycle to slow down. Aquariums are in most cases not clinical, and are prone to a number of outside influences.
The product is not an "instant fix" or a way to make it so that you do not need to properly cycle and maintain your tank. It is simply an additive that may assist you in culturing bacteria colonies in your tank. It is not going to turbo boost your bacteria cultures, as there is only so much area for them to affix to, but if your cycle is stuck in the ammonia or nitrite, even nitrate stage, this boost might work for you.
If anyone else has actually tried testing it, as opposed to dumping in a bottle and then noting no results feel free to speak up, I'd like to hear, but I was curious and actually did test it in as controlled a situation as possible, and did get results.... I'm gonna go with that for now. If you do not have anything to compare your main tank's cycle against when using a product (or not using a product if that is your choice), of course you will not be able to see results, there is no control to test it against.
There are several people on this board with different opinions of the product, and several of them have a lot of experience like fshhub. If in doubt error on the side of someone like him who has been in this hobby for years if you are concerned, they obviously have more experience than a new member to the hobby.