Using Playtest Monsters?

[EccentricCircle]

So I've just picked up the starter set and am planning a game in the not too distant future to try it out. My only concern is the slight lack of monsters. I've looked at the last playtest bestiary and it looks as though I should be able to use the creatures in that fairly easily with the final rules. But does anyone know of any problems that might arise from doing so?
I've only played one of the earlier playtest packets, so am not sure how much has changed between the last one and the final rules. Should the monsters port straight over? Or should I learn the last packet in order to do a conversion of some sort?
Many thanks.

[Envyus]

The math is pretty diffrent just compare some of the monsters in the starter set to their playtest counterparts.