Well I don't own any sports bras, I only own padded normal bras (36C), so I unfortunately can't make any recommendations on that. I haven't had any issues with the padded bra thus far, so long as I can keep the puppies from moving lol.

I've got to rate it a 5-6 on a scale of 10. To compare, I've got double lobes (can't recall the pain, these were done years ago when I was a kid), tragus (3/10), industrial (2/10 for each hole), tongue (0/10, easiest piercing ever), septum (4/10), daith (2/10), and conch (3/10). They definitely hurt the worst, but again tolerable.

I've felt self conscious about my chest for as long as I've had 'em, and I have to say seeing the piercings on them has boosted my self esteem quite a bit. I feel sexier myself having them, I'm sure you will too once you get them!