If you rub it really fast, the burning won't be as bad. Or you wont mind it as much. Not sure which.

I read somewhere that they were good for the digestive system

Don't think you can kill a hot pepper plant short of digging it up.

I know if I feel a stomach virus coming on, I indulge in a batch of Hot Salsa and it knocks it out before it gets going. Knock on wood, I haven't got sick enough to throw up in over 30 years!

They aren't hard to grow. I usually have 25 or 30 plants of various peppers. I kept 2 Carolina reapers, a chocolate scorpion, and a Trinidad scorpion over the winter this year. The hotter peppers take longer to mature so it's nice to know I'll have peppers early this year. I make all kinds of stuff with them from relish to smoked pepper powder. A little goes a long way. Here is a day's haul from last summer.
http://imgur.com/gallery/jLdK265

I have grown the ghost peppers from seed. I started them in march indoors and ended up digging them and potting them to bring them indoors at the end of season because they needed another 2 weeks to fully rippen. I saw fleet farm had them here already about 10" tall. They were to much heat for me to enjoy. Out of 8 that I tansfered into the garden only 2 grew well. We have a bit cooler climate here though because of lake michigan.

They (superhots)are not hard to grow, but you need to start them indoors early (Feb here) or the plants won't get enough heat units when they are ready to fruit and you will miss a lot of production.
Start seeds with bottom heat and get under lights as soon as they sprout.
They grow well in 3 gallon pots with soilless medium.

Can they be grown from start to finish indoors?

They do well indoors with a proper setup. You would need some decent grow lights and a fan for a plant or 2...more than that and you'll want to look into a serious hydro setup.
There are entire forums and FB groupsdedicated to indoor growing of superhots.

I think hot peppers help with joint pain. At least it gets your mind off the daily routine of life. Plus you can save money by not buying hot sauce. Some hot sauce is stinking expensive.