I grew it last year and really enjoyed it. It seem fickle to get going, but once it is set it takes off to 7' tall or more, and is a very pretty place to watch grow.
Besides the aesthetics I would say a couple things to watch out for as it gets going:
1). It is very hungry plant, so it does best in rich soil and it will exhaust the soil after it's done for the season. Cause of this I just plant mine in old tires and it always has enough root room to reach its full potential.
2). Assuming you don't plant it too late the leaves will turn brown from the bottom up as it nears the end of the season. This is a good thing, that means they're done. So let them sit on the stem and yellow-brown out and then pick them off before they go completely flakey. They should be pretty easy to break off at this point without damaging the stem. The browning will work it's way up the stem as the season goes on.
3). Try them! Just after taking them off the stem they aren't great to smoke, but you can break off a quarter-sized bit and chew it and tell how strong it is.
4). There's a lot of techniques to cure the leaves for smoking after they're done. I would go to youtube for this one. Someone once told me you need a whole curing shed to cure tobacco right, but that's BS. A shed just helps provide some economy of scale. You can also put them up in rafters or something - idk what's best for your situation. You might have to get creative.
5). At the end of the season they will go to flower. Some people will tell you that you must cut the flowers off to better help the leaves mature. That may be true, but last year I only grew one plant so I let the flowers go to seed and I still got a good amount of the leaves to yellow. But you seem like you have a lot of them going so I would just let one go to seed - you'll still get some leaves, but the rest you might want to cut the flowers off.
6). The seeds I used last spring we're kept in good condition. In a little 1 inch wax paper envelope, then folded into aluminum foil, then in a sealed plastic sandwich baggie, then in an envelope and kept in a dark, dry, and 70 degree place. But the old seeds did not germinate this year, not one. But the ones from last falls seed pods did. So the seeds may only last for one year.
I don't remember the variety I have right now, but I am growing it again this year from last years seed pods. Luckily each flower that you let go to seed (and there may be 20-30 on the plant at the end of the season) will end up containing 500+ seeds alone.
Rocket Mass Heater Plans: Annex 6" L-shaped Bench by Ernie and Erica