I just wear my normal nursing bra at night too, as it saves me getting changed! I find it is comfy enough (standard m and s one) and I'm a large D cup. we co sleep frequently and I often wake up with one or both breasts out where I have forgotten to re fasten the bra after a feed!
I really like these for nights. they are thin cotton so non sweaty and have no plastic clips to dig in, the elastic is gentle too. very easy to whip a boob in and out and they hold breast pads well. they don't give much support but not needed at night.
Am very glad you suggested those minipie as I have just ordered some . Figured I'd get some cheapish ones to have them in (baby can't decide if she's going to make an imminent arrival or not) and then invest later if necessary.
I use the Mothercare version of those Jojo Maman Bebe ones (at least they look exactly the same from the pictures, same crossover crop top design) - brilliant, nice and comfy, wore them in the day as well during the super engorged early days before my size settled down. Mothercare regular nursing bras are completely rubbish but those ones work.