KTMs are very durable bikes, but they do require a lot of maintnance
because they are made mostly for racing and are very powerful but because of that require a lot of maintnance. They are very good for stunting mostly because they are so light and agile.
A lot of my aged peopple stunt them here in finland cause of there durability and power.
To make them readyy for stunting you mostly need a handbrake and meyby a bar bolted to the backframe of the bike.
For the handbrake you need a
master with a nonsolid container to have room for the clutch. Also the
back brake you need to have a look at because theres not alot of room for it because of the rims. If it doesent have room youre just need to make the
handbrake for the same rear brake as the footbrake.
You dont really need to do anything else for them.
If the bike falls the bars mostly take most of the damage of the fall.
I have to say though if you break something on the bike the spare parts are very expensive. Also make sure to maintain the bike or else it wont last for shit.