Which SIs are these?

From memory, you liked the original Super Iridium. These Polsilver SI are almost identical, and they work well for me.
 
They're on a Perma-Sharp level for me, pretty similar in terms of sharpness but a little smoother and with nice audible feedback. I rarely get any irritation with these in a 34C, they seem to hit the sweet spot. Sharp enough to slice cleanly and smoothly through hair, but not enough to feel harsh or dangerous. They're not really value for money at $40/100, but they're as close as I think I'll come to finding the perfect blade so they're worth the price for me.
 
I found them smoother than the Astras, and about as sharp. But then I've had some Astras that were pretty rough feeling lately too. Could be just some of those rough shave days though.

Using my last SI at the moment and it is smoother, but not uber close today.

I really think there's daily variables related to the state of our face, and its responsiveness, and we're too quick to blame these variables on the blades.
 
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