Which rig is more efficent for mining?

[BitRock]

I am going to build my rig for scrypt mining. I have two different plans.   

Rig 1: 4 GPU (600kh each GPU)
Rig 2: 6 GPU (400kh each GPU)

I am wondering which rig is more efficient for solo mining and pool mining even both of them have same hash in total.

[Duane Vick]

Need more info.

What is estimated post-tuned power consumption of each card in each configuration?

What is power consumption of both computers before addition of gpus?

What cards are you going to use in each?

[BitRock]

Need more info.

What is estimated post-tuned power consumption of each card in each configuration?

What is power consumption of both computers before addition of gpus?

What cards are you going to use in each?

Let's assume the two different rigs have exact same power consumption first.
Which one is more efficient for pool mining and solo mining  in term of the amount of coin?

[mac-coin]

Is this a trick question?

If they cost the same amount to run and produce the same amount work, they are both equal.

Then it come down to initial cost,  But the cheapest might not have the highest resale value, so keep this in mind.