You see, that's exactly why I don't like to recommend DE blades, I find them very smooth.I don't like them. I find them quite rough and uncomfortable, and they shave no better than blades that cost a quarter of the price. Blades are such a personal thing, so YMMV.
No experience personally with any Kai DE blades, but the Kai Captain Titan Mild (Pinks) are great SE blades. Very forgiving and pretty smooth. I, personally, find Feather Pro's or Pro Super's preferable at the minute, but will definitely be cracking out my Claymore with a Kai Pink soon!
Since I wrote that I did actually try out Kai Blades. Noted immediately that they're slightly wider and thus more noticeable in milder razors. A nice blade but I'm happy enough with Polsilver SI, Nacet, Ladas, Voskhod etc. to not warrant a purchase of the Kai.Absolutely on the Kai Captain for SE's. A wonderful blade.
As for their DE blades I found them a great edge which gave a great shave. A better useable life than a Feather. Very much liked here. And then someone introduced me to the Polsilver Lodz
I'm midway through a pack at the moment and i'm not that impressed, my benchmark blade is a Feather, and whilst the Kai's feel as sharp they are no where near as smooth for me, and they don't last me as long as a Feather either, just 2 shaves compared to 3 from a Feather. I'm also finding that they are suited to a mild razor better than an aggressive one comparing across 3 different razors, being an R41, Fatip Grande and the ES Braveheart. I'm going to try the last two that i have in a Gillette Tech and an old type, i think they may suit the Tech quite well, but i won't buy any more.