OSCAR, nice cabinet!
I'm curious, what type of router bit did you use to cut out the sides?
At one point I wanted to do the same thing and I was playing around with a 3/8" solid carbide spiral cut bit and 3/4" MDF. I found that it got dull really quick and would start to do more burning than cutting (I was running the router at max speed; 30k RPM or so).