Is the HP OmniBook 3 good for everyday use?

Yes for browsing, email, documents and streaming. The Core 7 350 and SSD keep it responsive, but 8 GB of RAM slows it down once many tabs or apps are open.

Can the RAM be upgraded?

On most OmniBook 3 configurations the memory is soldered, so 8 GB is what you get. Check the exact model's service manual before buying if you plan to add memory.

Is the 17.3-inch HD screen sharp enough?

It is fine for video and basic work, but text looks less crisp than on a full-HD panel of the same size. If sharp text matters, compare with 17-inch full-HD laptops.

Can it run games or edit video?

Only lightly. The integrated graphics handle older or casual games at low settings, and short video edits are possible, but it is not a gaming or editing machine.

What comes in the box?

The laptop, a power adapter and the usual paperwork. A mouse and sleeve are not included.

How does it compare with a 15-inch laptop?

It offers a bigger screen and keyboard for desk use, at the cost of weight and portability. Choose it if the laptop mostly stays at home or on a desk.