We have owned a lot of ikea furniture over the years. I've never bought online though. IKEA is what I call the best of the cheap. Most of the furniture is particle board, though some is solid wood. It's the highest quality particle board I've owned - the bookcases are particleboard veneers, but real wood veneer - so it doesn't have that fake printed woodgrain. Since they store everything flat, sometimes the end of a box will be damaged and particle board doesn't handle that well, so when we went to the store, we always check every box exremely carefully for damage. I would be very careful of this buying online, just check it very carefully when it arrives for shipping damage of any kind before opening and send it back if it looked like anything was damaged. Check their return / exchange policy, since I don't know what it is online (in terms of whether you have to pay to ship it back if there is a problem, etc) however I know in store they take everything back and have a pretty good exchange policies (it just sucks to lug it back to the store). I did once have the stuff delivered (bought in store, had it delivered to the house) and I think something was damaged and they just came and brought a new one, no problem
I've been eyeing that Kura bed for years, its so cute! It's solid wood, pine I think (other than the blue panels), the other is laminate veneer. We have some cabinets from IKEA in that type of veneer. They withstood being shipped from Washington cross country and our mover wouldn't insure particle board aparently because it falls apart so easily, but they didn't have any problems.
I think they are generally much nicer than any other particle board furniture I've had or seen.