They work great for about 3-4 days of daily shaving for me. Luckily they are cheap enough that even 2 days use would be good enough.
In my book they are both almost the same sharpness. But the Swedish supersteel is ever so slightly sharper on shave 1. Something important to bear in mind though. The Platinum Lux being platinum coated gets slightly sharper on shave 2.I tried these for the first time this Saturday in my Dark Stag folding Kamisori. I had about three days growth (quite coarse and tough) and these cut through well on the first pass. After three passes I had a bbs finish with a few nicks and minimum irritation. I would say these are reasonably smooth and have a decent sharpness (above the Rapira Swedish Steel maybe). They will be going into my regular use pile for sure.