I will provide some background info. on the Seachem product to increase the general comfort level. First, let me say that trying to provide live bacteria in a bottle, stored under ambient conditions, is a non-starter. The bacteria are far too fragile and few would survive. However, under conditions of environmental stress or deprivation, many species of bacteria will undergo SPORE formation. Essentially they condense and toughen to form durable survival structures, designed to protect their DNA and basic metabolic machinery. This is what Seachem has done in the laboratory. After the spores are collected, a chemical inhibitor is added that prevents the bacterial spores from reverting to the original vegetative state. When the spore solution is added to the aquarium, the inhibitor is diluted and the spores return to their original, metabolically active state. Bacterial spores should be able to survive easily for at least three years under ambient conditions. To me, this represents a simple, logical and robust approach to rapid cycling. The species of bacterial spores provided in the Stability formulation is proprietary. For fans of Biospira (I am one), I don't know if it's included or not...but it really doesn't matter. All you really want to achieve is a stable population of bacteria which are oxidizing ammonia and nitrite. Biospira (and other bacterial species) are ubiquitous and if they have a growth advantage in the filter, they will eventually outpopulate the other bacterial species.
Regarding my personal experience with Stability, I cycled a pristine 350 gallon tank, with four large Dats in 8 days. Changes in ammonia, nitrite and nitrate were monitored with two different test kits/methods. I was quite impressed with this product.