2160x1400 Amoled display is one of the best (if not the best) available on a Windows tablet. Colors are great, and the screen resolution is very high making web pages, pictures, and videos look very crisp.
There is one single USB Type-C port and a headphone jack. For any other connections, you'll need to purchase an additional dongle (although then you can't charge it at the same time).
The keyboard isn't back-lit, and key travel is short. The keyboard only has two positions where it can hold the tablet (one near vertical, one near horizontal).
The (included) Surface Pen has a very interesting set of features - it allows for 1024 points of pressure, has an eraser on top, and when you click the eraser it will open Cortana (Microsoft's new voice assistant). It's magnetized, so it will stick to the left side of the Surface. The Surface achieves all of this via its new N-trig technology (replacing the Wacom technology found in older generation models). There's also palm rejection technology, so whenever the pen tip it close to the screen is will ignore all finger or palm touches.
The Surface Pro 4 comes in configurations from core M up to a core i7. RAM starts at 4GB, and goes to 16GB. Storage caps out at 256GB of SSD storage, which should be enough for most users. These are all specs that can be found in most laptops - even beating out some budget-midrange desktop options.
You can find a computer with similar specs for about half the price of the Surface Pro 4. You are paying a premium for the high-end build quality, for the engineering required to manufacture a fully portable computer, as well as for the high resolution touchscreen.
The Surface has a USB 3.0 port that can be used for a mouse to be plugged in, or you can plug in a USB hub or Microsoft's own Surface Dock, which has 4 USB 3.0 ports, audio output, Gigabit Ethernet, and two HD video ports. The Surface Dock allows for as much expandability (or more) as most laptops out there. There's also a SD card slot if you need more storage (current SD card sizes range up to 200GB, although this won't be as fast as the internal SSD speeds).
Windows has traditionally been a mouse-and-keyboard operating system. Finally, third party apps are starting to become more touch friendly, although it's a long, slow process. The Windows Store still lacks many big titles, which means the only option is to download the regular Windows version of most apps, which are rarely touch-friendly.
Having a keyboard option on the Surface 3 is much appreciated, and almost a requirement for most computer tasks. Typing out emails, commenting online or taking notes is not very easy to do on a 10.8" on-screen keyboard. The physical keyboard is about 1" shorter than a full sized keyboard, which is big enough to type fairly comfortably. The keys are pretty quiet while providing surprisingly long key travel for it's thickness.
Microsoft went with a magnesium casing for this tablet. The kickstand sits flush against the back when not in use, and the top antenna bar fits very closely with the casing. The keyboard is also very well engineered - key travel is great for such a thin body, and there isn't too much flex while typing.
While performance is good for most basic tasks, this tablet has a high price for a device with an Intel Atom processor and 2GB of RAM, especially considering that the keyboard and pen will cost extra.
The Surface 3 charges over micro USB, and fully charging it using the included cables takes between 6 and 8 hours. If third-party cables are used, the charging time increases.
The keyboard has quite a bit of bounce, and the connection isn't as intuitive as competitors. You need to press a button before being able to disconnect it, and the screen doesn't angle back very far at all.
For the price, the T100HA has good performance. Starcraft 2 will run at 64FPS on low settings, but when you up it to medium settings that tanks down to 18FPS. For comparison, the T100HA is about 10% slower than the Microsoft Surface 3.
On the tablet itself you have a USB 2.0 port, a USB Type-C port, a micro SD slot, Micro HDMI slot as well as the headphone jack. On the base you also get an additional USB 2.0 port.
Unlike many competitors, Asus actually includes the keyboard in the box. Microsoft, Apple and Google all make you pay at least an extra $100 to purchase the keyboards that their tablets use.