TN panels won't look good in portrait, not even in 2d. You'd need IPS panels for that, and i don't know of any 120Hz IPS screens.
btw, why get 3d screens when you know you can't use the 3d mode?
If you're only after the Hz you could get CRTs instead if you have the space. There IS a real difference that makes CRTs sharper for moving images(ie games). I'm not going to make this a full page post, but it's about LCDs "holding" the image in place for the entire frame while CRTs pulse them instead. This, combined with the persistence of vision inherent in our retinas makes CRTs sharper for moving imagery.