I don't believe those are the same thing. The premium eline R1 rotors are actually composed of more metal mainly in the webbing of the rotor. Plus there are more drilled holes in the rotor. R1 sells a cheaper version similar to those.
If you really want to believe they are different, go ahead. But I have way too much information to say otherwise.
R1 Eline = Centric Ctek
R1 Premium = Centric Premium
Discussed here in length with Tchuck:
https://www.infinitiscene.com/searc...-Posi-Quiet-Ceramic-brakes?highlight=concepts
I have gone over this many times before. I have ordered the Eline rotors directly from R1. What I actually recieved was a Centric Ctek rotor part #121.42080 (04 FX35)
ENGRAVED in the rotor.
does this look familiar:
Centric Powerslot Rotors
http://www.powerslot.com
vs R1 Concepts "Premium series brake disc with black e-coated hub"
The spec Image on R1 website is a direct copy from Centrics website, and even the descriptions are exactly the same
R1 Concepts: vs Centric Website
R1 is soo lazy they don't even change the description. I'm not trying to put down R1. But it is what it is, they sell Centric Rotors renamed under their name. Tchuck has the pictures to prove that he bought R1 Eline and Premium rotors. He recieved the boxes with Centric part #'s. Centric also owns Powerslot, Stop Tech, Posi Quiet, and C-Tek.
To top this off, R1 is located in La Habra California. Centric is located in City of Industry California, approx only 8 miles from each other. R1 orders orders their rotors from Centric. No other discussion necessary.