I've had the 519a dedome MDC for a couple weeks now and used around the house and on walks. I'm really impressed with the emitter. Color rendering is excellent and and the tint is pretty if you like a little bit rosy. Compared to my trusty MDC N with the 4000K XP-G2 it has a noticeably more intense spot, but it's not a huge difference and the beam is still a great all-rounder.
The low and high modes seem similar in brightness to the MDC N, but medium is substantially brighter which I'm not really a fan of. I already wish the MDC had lower low and medium modes so this one is even worse. It feels more like medium-high-turbo than low-medium-high to me.