This is more of a personal choice. The A-Frame drop-cups offer more support but limit your ability to move your breast around for comfort when nursing. The side-slings offer more movement but are not as supportive. Try one of each if possible to find out which works best for you. If you do not like either option, you can use the criss-cross sleep nursing bras if you find this style to be easier. Also, you can use a bra with a front open panel.  Overall, moms with larger breasts will find the A-Frame to be a better fit for comfort and stability. Especially in public, as moms don't usually want to swing large breasts around. If you are nursing twins, you will probably want an A-Frame as well for positioning. The side-slings are better for home use or for smaller busted women but can work for larger busts also.