I like them a lot. Took the sps a little while to get used to the switch but as you can see look great now and my electrical bill even lowered. I would say for the price and the fact they have a 3yr warranty and an est. 8yr life it is well worth the switch. I personally would not switch all bulbs to E-5, they are still very new to the market and not a lot is known about the ability of a full E-5 system to support a full reef.