Let's see. I would say go with the Nora. It has no defects what so ever. Nice tight joints, tight hardpoints, excellent paint application, great color, etc.
The Ivanon is sinister, but boring. Plus the only way you can be sure to get an almost flawless SV-51 is to get a V.2 or V.3
The CF is like the Ivanov, lackluster. But this little vulture is loose and can barely stand up. Missles fall off and the nothing locks well into place. The gunpod and cartridge do not interlock well.
Take this with a grain of salt, but definitely look into the Nora.