In the Seoul High Power Catalogue I noticed the next generation 3535 LED from Seoul. It’s not featured on the Seoul website, I don’t see any mentions anywhere on the net yet so the picture above is literally everything I know about it.
And it shows a bit higher output than Samsung LH351D with slightly higher voltage. Max forward current is lower which may be a hint of inferior thermal resistance.
But it is much easier to handle and apply in a flashlight because the usual centering procedure with common plastic center pieces can be followed. It is hard to beat the XP-L Hi in performance (but tint is bad) and the E21A in tint (but the package is bad), but this is somewhere in between, if the high CRI tint is any good I find it interesting.