I agree with Tom6897. I have done the Flexy. Its simple design encourages upgrades and tweeking. Unfortunately it is not a good design and is ironically beyond improving with "upgrades" like brass rods. Ikea's lack table is much better, although I am not completely sure they are made the same way. They are cheap enough to buy one for experimentation. If you flexy, don't use MDF. It sounds bad, period.
Flexy rack threaded rod material
It seems that brass is the universally accepted "best" material for the threaded rods of a flexy rack, but has anyone actually compared brass rod to any other material in a flexy rack in the same room and in the same system? I'm having a little problem shelling out 3x the money for something that is supposed to be better even though no scientific proof exists (or maybe it does, I just haven't found it).