I have been using one for a week. I replaced one of my 4 ATI bulbs the Aquablue Special with the E5 bluepop. The ATI bulbs was maybe 2 months old. At first I didn't notice a difference. I don't know if the E5 needs a break in time but after 3 days corals were deeper in color. Now after a week the details of torches,acans etc. are much brighter. I don't see any LED shimmer.