When people say "QBank" they're referring to the standard Kaplan QBank. Integrated Vignettes are usually referred to as "IV QBank." As for 1 month vs. 3 month, I would get the 3 month as I don't think it costs a whole lot more, and you will be able to use it further in advance of your exam rather than just for a few weeks. In addition, if you decide to push your boards back, you may lose access to QBank before you take the exam. However, if you really only have a few weeks to study, then 1 month access in addition to the released items should probably be fine.