Not going to up-pot for flower, I think we have plenty of root room.
As far as soils I use a base 50/50 mix of MG Organic and Fox Farm OF plus a healthy dose of perlite and dolomite. And MG ferts. Anybody care to stick around to the end and see what the wicked Miracle Grow can do? As you can see under the current MG regime they are struggling to survive.