Will this fit my laptop?

Only if your laptop has a 2.5-inch SATA drive bay. It will not fit M.2 slots. Check your model's service manual before buying.

Is it faster than the hard drive it replaces?

Yes. Any SATA SSD is far quicker than a spinning drive for boot and app loading. Against modern SATA SSDs, though, this older MLC drive is not a leader.

Does it work in a desktop?

Yes, through a standard SATA data and power connection. Most desktops have 2.5-inch mounting points or adapters.

Is MLC better than TLC?

MLC endures more write cycles per cell, which helps under constant heavy writing. Current TLC drives with 3D NAND are usually faster and cheaper for normal use.

What comes in the box?

The drive itself. SATA cables, mounting screws and brackets are not included, so check what your system already has.

Is it worth it over a current SATA SSD?

Mainly if you want the exact Dell part number for a service replacement. Otherwise a current Samsung, Crucial or WD SATA drive gives better speed and efficiency.