Strong companions in Skyrim

I've had a few companions who have died.

What are the best companions from a health perspective? And from a damage perspective?

I have tried a few of them, and I really don't see the big difference - they might as well be the same.

A good tip would be too take all their stuff. Replace it with a bow and some better armor, this will make them not run in to the battle and get hit by accident when in 'wounded' mode. Then they will die very rarely, but they will not make a good Tank this way.

It is quite useful if you use spells or a bow yourself.

As explained here, companians usually don't die.

Additionally, it seems that every companions does have the same stats. They also can use very different weapons and armory, you just have to give them a better weapon and they'll use it.