By work, I mean, are the bacteria viable and living, and are they useful species?
Brightwell has an entire line which does not require refrigeration - Microbackter7, Microbacter Clean, etc.
Dr. Tim famously has his line of start up and maintenance geared bacteria.
Ftitz is another one, which interestingly, seems to require the most care (most companies in Canada require overnight shipping when purchasing).
There's tons of information in the thread: Bacteria in a Bottle, Myth or Fact. (Sorry I can't paste a link from this computer)
Everything from here down is purely anecdotal.
There's a lot of debate about the topic. Jake Adams from the Reef Builders youtube channel has a series where he built and populated a nano reef in one day. He added Dr. Tim's One and Only to the tank. He added corals and fish in the first 24 hours and didn't have any major short-term or long-term issues.
Jake (RIP) was a very experienced reefer and there were other contributing factors such as live sand and the addition of livestock so it's hard to say if the One and Only kicked off the ammonia nitrogen cycle.
There's also a line of thought that the ammonia readings people are getting with standard test kits are overstating how much harmful ammonia is actually present. The supporting evidence here is that the issues seen with fish from a "bad" or "stalled" cycle aren't ammonia-related. People are using more advanced sensors to more accurately measure these levels but there isn't enough data to draw a conclusion. This obscures the effectiveness or ineffectiveness of the products.
Personally, I used Dr Tim's One and Only, plus live sand, Nature's Ocean water, and "live" rock (it was the dry type so I don't think it does much) and I was clearing ammonia in the first 24 hours. Without a strict experimental set-up there's no way for me to say what kicked things off in my tank. Furthermore, if it's marketing then I fell for it because I re-dosed with
Fritz with the idea that "more beneficial bacteria is better" but it was probably unnecessary.
The
Fritz I received was refrigerated and the One and Only was at room temperature. If it was the One and Only that kicked things off then there were viable bacteria in the bottle at room temperature.