IKEA does use a higher quality particle board than say Canadian Tire. Or at least it's better than what it used to be at Canadian Tire, since I stopped buying furniture from there (so who knows if it's still that bad). After one move, the old Canadian Tire stuff was wobbly while all of my IKEA stuff is still solid, even though I was feeling less patient last time I moved it and had a "if it doesn't survive, so be it" attitude.
Though note that I do tend to avoid the bottom tier IKEA stuff, since some of it does look pretty short term.