Help with Zeiss 24mm!

Thanks for your advice I'll go out shooting this weekend and see how the 24mm focal length fits!

I also like shooting wide (I tried a friends 16mm + UWA = does this equal 12mm?). I was considering the SEL1018 but figured that maybe the Zeiss 12mm would be a better investment (considering I already have two zoom lenses).

I realize that the 12mm and 24mm are completely different lengths. But considering the price of both (being a student), realistically I can only afford one at this time. In this case, would you suggest waiting for the 12mm?