I have a smaller bottom box and top box (off brand), but quickly overfilled it.
Like you.....I cannot afford a really nice box with the roller bearings on the drawers.
I watched Sears for a sale and got this one:
I know it would not work well for a professional who opens the drawers constantly, but for my home use it is fine.
Just watch the sales...check off brands for how well they are constructed and how well the drawers work. Ones that don't open well are very annoying when you are working.