Whether it lets you get more sleep depends on how many feeds you get out of one express. I had to express when my DS was tiny because he would fall asleep too easily while breastfeeding. For us, 1 express = 2 feeds in the early days, so I could express and go to bed for 4 or 5 hours sleep. Does your bub take both sides in a feed now? If so, then I think the others are correct, and it will be more fiddle than it's worth! But if he's a one-side-only man then it may work.

If you want to try, the first thing to do is express just a little bit (50 ml or so) and see if he and DH get the hang of the bottle. Get the slowest teat you can find, and stop and start the bottle feeding so it's more like a boob. Don't jump in at the deep end and express all you've got only to find that he won't take the bottle!

good luck!