Your general skills are great, modeling, photo matching etc... But I will agree with Leonardo, they don't look Maxwell...
I think the final images will look great, so work on your textures and you get a really nice result.
I won't sign it, if it is not a piece of art.. So far, I haven't done any...
Revit Architecture 2012, Max Design 2012, AutoCAD 2012, Moi3d, Maxwell, Octane ... and many working hours