Does anyone have any experience with cups sewn into their dress or with a plunging-back bra? My dress is too low-cut in the back for a regular strapless bra (see below), and I was planning on having my seamstress sew cups into my dress... until I saw the plunging-back bra below on Pinterest. Now I'm no sure which to go with.
I prefer the idea of sewn-in cups because I know my bra won't end up showing in any of my pictures and also because I think they will be more comfortable. But I am a little concerned that, with the top of my dress being so stiff, my ta-ta's will end up making an appearance at some point in the evening. They don't exactly fill out my dress-top, if you know what I mean. =/
Does anyone have experience with sewn-in cups? Do they keep things pretty secure as you move around? Or would I be better-off going with a bra similar to the one below and hoping it doesn't show?
Thanks in advance!!

