First thing the biggest photosynthesis peak is from 420 to around 440, this is why I use 445 royal blues instead of 450, and that has nothing to do with PAR, PAR is the amount of light you hit the tank with at certain depth, wavelength is the color of the spectrum.
Yes, If you have enough par with blues you will grow color but clearly corals use the rest of the spectrum.
Expensive lights are actually very bad, yes radions are not as good as the hype, they produce so low violet for the amount of blues that is insane, different violets will make more fluorescent proteins shine as well.
So yeah, if you don't want to build your LED's go with something cheap like the Vipar Spectra's. The first thing is PAR for growth and then for the absolute best color that is where wavelength plays a role.