Unless anything has changed MAD, vinh iirc said the benefits where not enough to justify. Throw maybe a little more, loss in lumens so i believe the dome on is the best option all things considered. Certainly wait for vinh to confirm either way. Dome on, you get a pretty much cool pure white beam, large hotspot and very bright spill. Honestly, i do think this is an awesome LED(sst40) for this light. Really good strong beam with enough throw imho.