Chastity and orgasm denial discussion

I’d like to ask some questions before ordering my little cage. First of all I’ll most likely get a silicone one with pink color, for some added humiliation. Pretty much like this: d5232fbda18e0165d9ef3960e276d634.image.300x300.jpg **1)**The entire chastity is 3.66inches and 2.56inches internally. I’m 4” flaccid and almost 8” erect. I believe the size is fine. Do you think it’d better if I get a bigger one, or this chastity is okay? **2)**It seems that a lot of people use lube/oil/baby powder especially at the beginning. I guess it is used to prevent injuries from the erections? Is it applied at the base of the chastity/around the ring? **3) **Also why do most people prefer steel cages? Thanks in advance.