I'm curious about their products. I haven't seen any bad reviews yet but I haven't seen a lot of reviews in general.
I'm looking for some new saison strains to use in addition to 3711 or instead of 3711 just to keep some variety in my beers. I suppose most of the saison strains floating around are either cultured from commercial beers or harvested from yeast banks and repackaged for homebrewing so neither is really "new".
If you search HomeBrewTalk and Reddit (/r/homebrewing sub), I have seen quite a bit of review of almost every strain they offer. Check them out if you get a chance.
So far as not being "new", I would probably disagree on that point. I think it's a huge service to offer strains that were previously not available to homebrewers and almost all craft brewers in pure culture. You can culture dregs from a bottle, but the important thing to remember is that pure culture from a lab that has zero tolerance for contamination is far superior to something grown up from a bottle in which there is an acceptable level (albeit low) of bacterial/wild yeast contamination.
Speaking from personal experience, I would say their Saison Blend and Wallonian Farmhouse are definitely "new", as there was nothing like them on the market before they showed up. They both produce profiles that are unique and, now thank to the folks at The Yeast Bay, easily accessible!