Can't speak personally about the specific heads but as with any used buy I would suggest getting them checked by a good head shop. If they are in good shape then the cost of checking them over will be minimal, if not then better that you know before they go on, may need to spend a bit more to have them setup and good to go but just do it if its minor fixes IMO.
What are the cc of the chamber, the runner volume, the max lift and the spring pressure are good things to know among others, you can confirm some of these on your own via model number. It is always best though to cc the chambers so you know for sure what you have, maybe the heads were milled or messed with in some other way.
good luck with em.