Personally, I'd wait for New Releases then buy New Blood.
Kinda been asked and answered so many times...
it all goes back to what you're looking for.
Personally i stick with that 295 credit one
some ppl swear by NB packs
some go for whatever urdb says gives the most value in clintz
some go for more rares
go to urdb.kirlad.net and make your own informed decision
Oh and NB packs should be bought on release fridays
I would suggest Nightmare as you can get Endora the wicked witch.
NB if you want the new cards or elite (Nightmare, berzerk, frozn and 1 more).
You're in luck! Nightmare packs are here! Plenty of witches there.