In my experience as a piercer I have found that a small barbell, or 1/4 turn/curved barbell provides the most stimulation for clients with this type of piercing.
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It depends on the shape of your clit and your hood. I have a small curved barbell with an oversized bead at each end and this presses pretty well on my clit. However, I have never noticed any increases in pleasure or ability to orgasm from being pierced. It looks pretty and guys love it, but sensation wise it hasn't made any difference.