I just used K-97. Fermentation took 13 days to reach final gravity at the relatively low average temperature for this yeast of 53 F. Bottled 11 days ago. Popped the first bottle 2 days ago. It came out great, I'm very happy with it. There is a slight haze -- the yeast needs extra time and/or gelatin to help it settle out. I used gelatin in the primary but honestly it wasn't as effective as I had hoped, not sure why. Still tastes a little yeasty / bready from the yeast. But other than that it is very clean tasting, zero diacetyl or sulfur, and no real noticeable fruitiness, at least when fermented real low as I did at 53 F. It did NOT turn out with an odd tartness as I have experienced with many other dried yeasts; yet on the other hand, I mashed relatively high at 5.5 and did not adjust pH in the kettle either, so that may or may not be part of my satisfaction. Note: I have theorized that this yeast is nearly equivalent to Wyeast 1007, and based on my experience with both, albeit separated by a few years, the K-97 seems to have performed VERY similarly to the 1007. So yes I still think these two are very closely related to where they could be considered “equivalents”. YMMV.
Cheers, hope you try it and enjoy it as I have. I will not hesitate to use it again in the future for beers that I want to be clean, bready, and lager-like. Potential drawbacks are not much different from Wyeast 1007 or 2565 -- not the quickest flocculation, hazy, some yeasty breadiness, at least for the first couple months, after which maybe most of that should settle out.