here the the set up that i liked.
i had/have a EZ2Nurse twin pillow, i dont use the extra back section, i use a nice pillow of mine buckled up against my back instead.
in the first months i would sit in bed,
put another pillow horizontally in the small of my back,
then buckle the twin nursing pillow, with my nice pillow upright against my back inside the strap.
then a large boppy style pillow under my knees curving towards my body, this was the great trick i figured out
not only would the bobby pillow raise my knees up and take strain of my back, but the wings of it sticking out on each side supported the edges of the twin nursing pillow and kept the babies safely on it and some of hte weight off my thighs. i could reach them and lift the m into place one by one once i got set up and i could even sleep like this with them after a nursing.
i later got fancy and added a pillow over my lower legs that proped up an iPad and i watched 6 seasons of Bones on netflix over the next few months with my headphones on while they nursed or slept. yeah i spent a lot of time in that set up, it was really comfy. i also figure out that there was enough of a gap between the firm edge of hte nursing pillow and my stomach to pick one baby up and let them "sit" on the edge with their feet tucked down between it and me and lay on my shoulder for burping, cuddles one on one or whenever, while the other one slept soundly or kept nursing.
when i did have them on two boppies, i think i vast preferred the freedon of two separate ones, there was stages of steeling binkies or one kicking around while the other dozed off that having them atached would have made lot harder. plus there was a lot of times where dad would coem to bed or on the living room floor and we would both pull a baby and a boppy up and get some tummy play time with one of them. i hapened to use these Cuddle-U Nursing Pillow rather than the boppy brand (i actually had a boppy too since i got them all super cheep at a twin consignment sale so i didnt have to take them all in and out of the bedroom 3 times a day. they are a bit bigger, and i liked the variety that afforded us on uses, and the strap, while funny to use when they are super tiny can in handy a lot as they used them for napping later on