Ypu will be more than fine with any strain. That's only my opinion. I grow in a 3x3x5 and I run 4 plants at a time with advanced nutes. THEY GET BIG. Here's what you have to plan for.
LST on a any strain that tries to dominate the others in size. And height differences. I use 5 gallon buckets cut to different heights. That way you don't have one go vertical on you and have to push your light up too high causing the others to suffer.
So in closing. Yes run 4. Train them for an even canopy and have a plan to lift the shorties up to the tall ones level