I had wind deflectors on my old 4/4 . In theory they should work but I can't say they really made much difference, nowhere near as noticeable as having screens on or off. Personally I wouldn't bother.
An extra or an inch less can make a huge difference though.... I'm talking steering wheels here! I had a 13 thick rim motolita in my plus 4, didn't like it at all. Seemed far too small to me and quite 'go carty' , put a 15 inch flat 4 spoke on and it was fine. I wouldn't go smaller than 14 but maybe that's just me.
I remember the fad for fitting wide tyres and small steering wheels.. Did the same on my MGB, all it did was make it heavy to steer and nowhere near as nice as the original set up.
