I haven't grown it, but I know of it and have grown it's "parents". Dwarf Wild Fred is one of my favorite dwarfs, and Beauty King is very pretty and tasty. Chocolate Lightning is among the bigger of the dwarf tomatoes. It could stay around three feet, but it can also hit five feet if happy. Fred can hit four feet when happy, and King is an indet. Better to be prepared for a potential max height than underestimate Lightning.

I would recommend a 15+ gallon container. Use cage support types. You are going to need supports for the branching and fruiting habit, and stakes aren't going to quite cut it. Do not use standard cone shaped tomato supports- those are great for peppers but not so much for anything other than very small growing tomato plants. Chocolate Lightning will likely be too big for it. If your tomato ladders are tri-fold, use two and make it a six sided if you can. Sometimes the trifolds can be a bit small on the inside for larger dwarfs. If you have your container in an area that can catch goodly wind, I would recommend staking your ladder.