Hardly a Rapira expert, but have used them all, with one exception, and long ago arrived at my favorites (in order).
1. Rapira Platinum Lux: A sharp, smooth blade that holds up from shave to shave. For me this is an exceptional blade and one of my favorite blades.
2. Voskhod: Marginally not as sharp as the Platinum Lux, but exceptionally smooth. If the Platinum Lux is an exceptional blade, the Voskhod is a good, yeoman blade.
3 Rapira Swedish Supersteel: Sometimes a bit rough on my face, sometimes it's good. As as I recall it's not as enjoyable for me as the Platinum Lux or Voskhods.
4. Rapira Super Stainless: Another good, yeoman blade, not quite as sharp as the Platinum Lux and not quite as smoother either. Yet this blade gets the job done. Bonus points for the cool pink and blue box.
5. Rapira Super Stainless Chrome: This blade seems to be newer on the US shave scene. I haven't used this blade yet, so can offer no opinion about it.
6. Ladas: Rough, tugged - not a good blade.
Rapira Platinum Lux vs. Rapriare Super Stainless vs. Voskhod?