I'm no fan of the combo valve used in this filter, but seeing as it's not an automotive application I suppose not as critical. Based on the fact that Wix doesn't use them on their Wix branded 'automotive' filters, they must think that to be the case.
I don't like to make much of 'wavy' media, because as long as the media isn't compromised, ie., torn or breached, it's really only aesthetics/appearance issue. That doesn't affect performance.
Here though rather than a wave it looks more like bent media, either from assembly compression(slightly different pleat width) or some type of use compression. I would be more inclined to believe the former than the latter. Again though, as long as no breach, no biggie, did it's job.
Curious though, can't this application fit a longer automotive filter application? That's what I use on my Kohler lawn tractor engine, after the shorter Kohler oem came off. I use the Napa Gold 1348 (wix 51348), 3614, 10241 equivalent. That way you get all the features of the automotive filter, more media, and they cost much less than Kohler oem.