A built-in or integrated fridge will usually have less space than a full size fridge of the same width. I have a 36" Liebeherr integrated fridge with (2) 36" Ariston refrigerator drawers next to it. We are are a family of 5 and so far it works well for us. The 2 extra drawers have a lot of room and we use them for our beverages and that leaves a lot more room in the actual refrigerator. The freezer space is smallish, but still holds a good amount if you are a good organizer :). It also has an awesome ice maker that makes nice little cubes of ice. We do have our old fridge in the basement for extra storage (mostly for holidays or parties when we need more room)

We have a built-in 30" all-fridge (Thermador Freedom Column) and two 24" GE Monogram fridge drawers -- and they both are packed, all the time! (We also have a 30" all-freezer in the kitchen plus a chest freezer in the basement.) We did our kitchen ~four years ago, and our two children are now 7 & 5 -- my point being I only have two small children (not voracious teenagers). Granted, we are strict vegetarians, so we have lots (& lots) of fresh produce. But both my husband and I are of the mind: you can NEVER have enough fridge / freezer space!

freezer on left, fridge on right: both have faux drawer fronts to help break up the plane

stacked fridge drawers are just to left of sink [on right side of pic], with the fridge on the far left of the photo, just next to ovens