Im currently running a FluenceBioengineering SpydrX Plus in a 5x5 and a HLG 550 V2 Rspec in a 4x4.And i can tell you they are both great.But i like the fact that HLG uses less electric 480 watts compared to 660 watts from my SpydrX Plus but the heat sink needs a better design.Gives off more heat...