I don't think there is any benefit from radiation exposure, its just a fact of life. The article I linked to above showed just how silly our views of radiation were- according to the EPA whole sections of our planet are in need of cleanup due to natural radiation.

I, personally, would try to minimize my exposure- but I would not panic if exposed to 10 times the natural background for a while- I have probably had the average exposure to radiation... aside from numerous long airplane flights... maybe I had a little more exposure to tritium than most people but thats it- I certainly am not worried about it...

Radiation is just a fact of life- for some reason people seem to think 'radiation' is - by definition- unnatural... That is simply wrong- the vast amount of radiation your body will be subject to is %100 natural.... It isnt 'good' for you, but it isnt absolutely bad either... Next time you walk under the sun try not to panic when you realize that the UV is tearing apart your DNA...