Container Size

Wanting to stay within legal medical limits, I am upscaling the size of my container, while downsizing plant number in an attempt to keep yields similar to what they had been in the past.

Has anyone ever used the 20 Gallon "keg tubs"? I was planning on using them, but was wondering about opinions on how many (and size of) drain holes to drill, if I should line the bottom with perlite, or hydro ton. Also I was wondering if these are just overkill, and if I should stick to 12-15 gallon size. Factors I am thinking about are amount of nutes and water used, getting rid of a lot more used coco very two or so months, and if the plant size warrents needing such a large container.

Info: I will be using roots organic coco, with house and garden coco line.
I am vegging these for about 2 1/2 months, but would like to keep the containers for plants that will on average veg for 3+months.
Yeild wise I am shooting for one pounds per plant. I have done 1/4 pound+ in hydro in 3 gallon containers vegged for 2 months, so I think this could be a reasonable goal. I will be happy with anything over 1/2 pound per plant.

Thanks for reading and advice.

Only included yield goals to give as much info as possible. Do not want to come of smug or boastful.