Kenaz finds them akin to Hot Spirits in Vodou. In this I agree. They are quick to work but volatile. I would not go so far as to say Corrosive, though some are. Asmodeus was when I worked with him and I would never do so again. Bune and Vassago are more chill. And indeed the book itself gives hints as to which ones are easy and which ones are a pain in the ass.
Frater R.O. who I normally agree with in many ways has pointed out that the main screw up with how he worked with them lately was on his end: not supplying a specific plan for them to operate within. Very true. He did however seem to say that there was not much difference between the spirits of the Goetia and the Archangels or Planetary Intelligences. This I totally disagree with. There is a Tutelary and uplifting role to the higher spirits that the Goetia just do not have. They can behave in unpredictable ways, but not usually in the same manner. When things go wrong with Angelic magic it is pretty easy to address and fix. When things go wrong with Goetia, they tend to take some of the worst possible forms - just like working with some of the HOT spirits of Vodou or even some of the Dregspa - wrathful spirits of Tibet,
Anyway, I respect everyones opinion. In a way, I wish I had left out the Bune thing on TSS, it was however the fulfillment of a contract with the spirit.