Mann makes quality looking cartridges, this one another good example. And no doubt they fit well in their specified application. Based on observation, fit in housing tends to be important in cartridge use.
As for pleat wave consideration, I'd say there's degrees of waviness. Here, I'd call it more very minor displacement from overall straight uniform pleating. No comparison to some the wavy pleating seen in anecdotes over the years. ''In my observation', some brands seem flogged here for it more than others. Personally think wave mostly an appearance thing than a functional one. As long as doesn't result in a tear/bypass issue. all good. That said, based on reading comments, seems some really like China coo filters with straight pleats.
Thanks for pics.