The box weighed forty-two pounds, which I knew because I put it on the bathroom scale after the delivery guy left. I slid it out on the hallway carpet—the bottom was raw MDF, no glides, so it scraped. That should've been my first clue.
The casters lie
Most under desk cabinets come with four wheels, and you think that solves the rolling problem. Then you lock two of them, and the thing still drifts when you type hard. I found out why: the locking mechanism only catches on one side of the wheel. Press the pedal and the caster stops, but the other side still spins freely. So my cabinet walked an inch a day until I wedged a rubber stopper under the front.
Test the locks before you load it. Put weight on it—a stack of books—and push. If it moves, you're going to be chasing it around your office for a week.
Drawer depth is the trap
The cabinet I bought looked perfect: three drawers, paper tray on top. But the drawers are 10 inches deep. That sounds fine until you try to file hanging folders. Standard letter-size hanging folders are 12 inches. So nothing hangs, everything just piles. I ended up using two plastic bins inside each drawer just to keep stuff from sliding.
Measure your actual stuff. Not the space—the stuff. I didn't, and I've got a draw full of random cables because the drawers are too shallow for printer paper.
The one decision that actually matters
Wheels or no wheels. That's it. I bought the rolling version because I figured I'd move it for floor cleaning. But I never do. And the wheels add wobble. Every time I lean on the cabinet to stand up, it shudders. My next one will be stationary, with legs or a solid base. Because once you park it under the desk, you don't roll it. You just trip over it.
If you're still desk hunting, check out this Cheap Writing Desk: Three Things That Actually Matter When You're. And if you're thinking about storage, I wrote about the sizing trap with Wooden Shoe Storage: The First Week Setup and the One Measurement. Both taught me the same lesson: measure the drawer, not the width.
The real test is whether the cabinet stays put. Mine doesn't. Yours should.