Macscale
Aquarium Advice Addict
Par and I believe pur (I think that's it) values are the real measurement of intensity.
Par doesn't really do much with LED. It's mostly PUR you are looking for.
Since no one answered the OP's questions about the Radions, I will.
Right now there are 3 generations.
Gen 1- obviously the first
Gen 2 and Pro- Both are the second wave.
Gen 3 | x30r pro (something like that)- The newest additions.
Doesn't matter what you get really. Just the newer one will have nicer stuff. Expensive though.