3x8x4 grow cabinet T-5 or T-8?

Hey there people, I'm setting up a cab that is 3ft wide by 8ft long by 4ft tall. I want to use T-5 or T-8 lights but am unsure of how many I would need. Any advice for me out there?

Higher wattage= more nug. If you can afford it, get the t8. Unless you have one plant, which you may only need the t5. Up to you.