I have some on my Lakland 44-PJ. I mirror the experience of them really not being what I was expecting, as others have mentioned, way more 'roundwound' in feel than they're perhaps marketed as. That said, for me, the texture wasn't really a make or break.....I mean as long as they don't shred your fingers right?! I would put them on par with a Nickel string, roundwound, but easy to play. My undertstanding is that IMA requested a little more left on the string than their Super Polished....so that makes sense.
Tension wise, I experience them more in the realms of the La Bella RX Nickels than their RX Steels, with the latter being a little too stiff for my liking. I wonder whether the polishing process takes a little stiffness out of the string, which is perfect for my preferences.
Sound wise I didn't experience them as zingy at all, I thought they were like nice played-in rounds, kinda like a slightly aged nickel (IME steels don't age as well as nickels).
So I gigged them and they were great, really enjoyable to play.
My main criteria was longevity, so we'll see where get to on that, IMA reckons he got a solid year out of one set, and he gigs WAY more than me....so I'm hopeful.
Watch this space.
Si