I've had the Marinade express for maybe a year now. I use it for processing all meat proteins and sometimes fish filets. Its a fun tool for sure. It has some really nice features and adjustable dividers.
Its can really be used to do more than marinating too. You can buy these pre-made marinades or a flavorless marinade from the company sold under a patented name grovac. Its really nothing more than some citric acid and salt. I use food fresh sometimes. Using flavor enhancers with a tumbler is ideal. my favorite is FAB from The Ingredient Store.
The actual unit is very well built. Made just as well as my Blendtec and Polyscience SVP.
I am in no way affiliated with Marinade Express. Hope that helps