Much depends...of course.
My favorite position to get it hard above all others is rear, still.
I enjoy really hard thrusting etc etc with averages in lenghts (havent experienced yet 7" and 8" thou).
In a penis long in lenght (9") is much different... if I go harder with him I will "loose" the many sensations its long thrusting inside me would give me, than with him I would go steady deep and slower, of course...and its just amazing the thrusting seems having no end and goosebumps starts as the 1st initial long thrusting starts... until cum (at least to me).
Another thing to me, if a penis has foreskin is another sets of more sensations on top of it all, to me, a foreskin penis when thrusting harder is different then one without foreskin...it does very much vary from individual men and his penis make up and my feeling of it all.. as how it feels hard with him and others etc.
updating my own sensations..having had another 9 length I did get to experience harder thrusting..still can't change much anything else from my post..those long lengths are amazing for rear! and foreskin sensations going harder is very unique...
Oh man..I love those old threads..and miss lots of you people! x