Hmm, well I can't give quite as accurate price info as an Australian member could so I'll leave that to someone else.
What I can tell you is that Carnage and Venom are not yet in the MU line. They come from the Spiderman line and there's a list of the releases
here. There is a second bulkier Venom coming in the line too but this site has no pictures.
As for actually recommending them? It's really up to what you need them to do. Sculpt and scale wise they are fine. Articulation is worse than MU though. Venom has no knees or ankles! Carnage is serviceable though but neither are stellar. Hopefully that helps some.