IKEA stuff is also relatively easy to "harden" with some extra strategically placed metal brackets from Home Depot. For instance you can make a particle board bookshelf very sturdy by screwing some L-brackets on the back corners. Corner braces screwed under the shelves will likewise keep them from bowing under the weight of books.

It's a few extra dollars and will make the pieces survive a move and just generally feel sturdier. It's not a replacement for "good" furniture but will make the cheap stuff much better.