It's very sturdy for being particle board, feels well made. The raising and lowering mechanism is smooth- comes in 3 stages and feels solid to me at each stage (it says there's a 20 pound weight limit on the raised section). 

Unfortunately I can't really use the raising mechanism because I don't have enough legroom with the desk against the wall unless I put my monitor in the corner. So I wish the desk was deeper. And having the monitor in the corner is not ideal because now my knee rubs against the bracket that supports the raising mechanism. So I'm going to try to modify it to remove the mechanism- which will make the desk immobile but will make it a lot more comfortable in the sitting position. And there's a 1-inch gap between the main desk and the L because of the raising feature, which is also a little uncomfortable with the monitor in the corner. So I would have been better off with an L-desk that doesn't raise or lower.