Mature Metal discussion

I’m trying to decide between 1 1/4 and 1 1/2 length. My penis measures between 1 1/4 and 1 1/2, but rarely hits 1 1/4; most of the time I land just a notch or two below that. It’s usually about 1 1/2 when standing, but shrinks up while sitting down or bending over. Sooooo I’m worried if I choose the 1 1/4 size, the head might press through the bars and scrape my clothes (some lace panties can be painful!). Should I trust the “go 1/4 inch lower” rule or play it safe with the 1 1/2? I really want a PERFECT fit without any extra room; tiny is my goal. I’d shrink myself down if I could!:) Thank you all!