While I havn't found the RS-2s bright, only clear I must say I find them warm for Grados. Clear with warmth from the articulate yet resonante bass lines resonating within the venue. I did audition the RS-1s although not "in home" with my associated gears, however I thought them to be brighter by memory. However, I do allow for others opinions to be fully valid, but I thought in all fairness to balance out these statements above, I just needed to state clearly, this my opinion. The RS-2 IMO is warmer and less bright than the RS-1 in my experience. As always, associated gears downstream maybe a large part for these differences of opinion.
I find the RS-2s HFs to be extended yet silky smooth and refined and most realistic in the reproduction of cymbals of all my cans; Certainly less harsh than the 990s followed by the 701s whereas the 501s, which aren't nearly extended at all as to get into trouble with harsh HFs, yet their cymbals aren't at all well represented in their presentation.
Certainly then, the midrange upper mids must be the focus of this obeservation and deviation of opinion as to which is the brighter presentation . I'll leave that for others to be specific with and again, point out the roll of associated gears perhaps, being largely causative as to our experience and opinions.