Number 1: Go with The attitude seed bank. They are badass reliable and I have a 100% germination rate with them so far
As for going for 4 large plants, what kind of light are you going to use? If your going with CFLs your going to need them closer to the plants so sativa isn't a good choice as it grows taller so your light wont reach the lower leaves. If your going with a higher power light option like HID or HPS then it wont matter because you will be pumping out more light.
I love me some hybrid mixes but lean more towards sativa.
One you gotta try that I am growing right now is BARNEYS FARM RED DIESEL FEMINIZED from attitude seed bank, I have red so much on red diesel, its got this dank sour grapefruity taste and hits you like the fist of god.