I've had some enquiries regarding the units beside my 4 x 4 expedit from Ikea. The drawer units are called Alex. I have four of them stacked two high. I've had these units for about 4 years now and they still look great. I have stored punches in the drawers with no problem with the weight. Most of these drawers are filled with wood mounted stamps. I can stack two stamps high in the narrower drawers and three high in the taller drawers.
Here is a link to the ikea website for these particular units.