Is 1080p sharp enough on a 27-inch screen?

It is usable for video and casual use, but text and fine detail look softer than on a 24-inch 1080p or a 27-inch 1440p monitor. If you read and write documents all day, a higher-resolution panel is the better pick.

Is the 100Hz refresh rate good for gaming?

It is a clear step up from 60Hz for smoothness, and fine for casual and console play. Serious competitive players will want a faster IPS or TN panel, because VA smearing shows in fast motion.

Does the curve help or hurt?

The curve adds immersion for films and games at a close seating distance. It can make straight lines look slightly bowed, which bothers some people doing design or spreadsheet work.

Can I mount it on a monitor arm?

Yes. It has 100x100mm VESA holes, so a desk arm or wall mount replaces the tilt-only stand and adds height and swivel adjustment.

Does it have speakers or a USB hub?

No. It has HDMI, DisplayPort and a headphone output, but no built-in speakers, USB ports or webcam, so plan for separate speakers or headphones.

You get the monitor, its stand and base, and the cabling Samsung ships with the model. Check the listing for which cable is included, since HDMI and DisplayPort cables vary by region.