I just noticed that the S5 comes out in a week or so, since it would cost the same for 2 S3 or 1 S1, I probably should just wait and get a S5....
Depends on what you pay for electric and if you already have PSU's or need to buy them as they need to be figured in. You can buy the S3's used at a better price than new and nobody knows yet just how well the S5 runs.
I also think you mean to say S4 instead of S1?