All these height threads on TSR...I reckon you can simplify the answer
1. Girls prefer taller guys but its not a deal breaker.
2. Girls 'ideal' height preference in guys is probably somewhere 6ft-6ft 3. 6ft has psychological connotations of being the barrier at which 'tall' starts.
3. Posture is very very important ie you get a lot of submissive beta male type guys who are over 6ft but slouch a bit and project bad body language, which negates their height. If you get a guy who is over 6ft and stands tall then it gives him a commanding physical presence. There's a Uruguayan guy at our work who is quite slim build and probably about 6ft 1 but he stands tall and walks with a certain assurance and it gives him a commanding air even though he's not built like a tank.
4. Once you get over 6ft 4 it usually looks awkward and lanky BUT when you get a guy who is tall who is also an athlete (eg plays rugby/rows etc) then that looks the best of all. Taller guys who go to the gym look great, when you get 5ft 8 gym rats they always look a bit Popeye and walk with a funny waddle, when you get a 6ft 6 gym rat they just look lean and ripped.
5. Being tall as in over 6ft 4 brings its own problems though in terms of fashion, ie you have to get stuff specially tailored, and it limits options for dress sense.