Hammerer: dafman
Honestly, I couldn't tell why you originally posted here and you certainly didn't pitch the original post in the way you explain.
You say you plan to switch on the basis of lowest cost. If low cost is your priority then there is no doubt that 2 Degrees and Skinny are your best options. But cost is not the whole story as others have pointed out. For example, Skinny is often the better because you get the Spark network rather than the more limited 2 Degrees network extended by using Vodafone's network.
Also, responding to your original post, it's very hard to comment on what is the best deal when we know nothing about your partner's (or your) actual needs. If low cost is your priority then I would be looking at what I need before looking at what is available. You may not need either plan you mention. Your comparison would also be moot if your partner never uses anywhere near the talk time and data on either plan.
Ok, this is why I posted - to discuss one supplier's offering versus another, and what I thought relative value was. In return, I get useful input from other forum users which helps round out my view before I make a final purchase decision. Is that not why many people post on forums, or am I missing something?