TLC's product could be as effective as they claim, but there is nothing on their webpage or "independent tests" that convinces ... I realize that companies are always concerned about proprietary formulae but this does not negate the possibility of running decent studies.
There is no comparison between the bacterial hodgepodge to be found in a handful of garden or other soil, or yogurt for that matter, & laboratory designed, controlled fermentation runs of bacterial cell lines ... I rather doubt that any of the commercially available products are not subject to some production guidelines - at the least there is unlikely to be any Closteridium or Pseudomonas etc present in that nicely labelled bottle.