Viparspectra 1000w distance

Hey guys new to led..have come from 600 HPs and MH grows and wanna try out led...tho I'm out of my depth and asking advice on a couple things...so..a mates not doing it any more he has more then enough for some time he reckons so I have a couple choices...there viparspectra branded and 50 Bux cost..my choices are a 1000w full spectrum AVG power consumption is 230+3% what ever the plus 3 means...and 2x600w AVG power consumption is 132w+3%..both have duel chip high out put led...so I can have either one what would be the way to go?..and he tryed exolqing distance to 4 plants which he lost me ...could some explain the optimum were to start and were the final distance is I should reach...I'm using a 60x60x90 with 90 being the Hight of the box....my idea was 250w MH cooltubed that I start seedlings with and placing either the 2x600 on the sides or one side and rotate the pots or the 1000 on the side and rotate the pots or should I do the opposite..I'm chasing as much veg growth in 4 weeks as I can..and mabie flower just under the 1000led or the 2 600 but I have no idea if that will flower good compared to 600hps