Difficult to answer since it depends on what you want to do with it.
If you want something portable and is actually a good and less expensive competitor to a Surface Pro 4, then consider the following Acer Switch Alpha 12 for $650 (currently on sale from Costco for $650). It comes with a Core i5-6200u, 8GB of RAM and 256GB SSD. It comes with a keyboard (which has backlight) and the digital pen which is normally sold separately. While it is less expensive than Surface Pro 4, it also has a somewhat shorter battery life which generally ranges between 5 to 6 hours based on the all written and video reviews I have read and watched. The Surface Pro 4 generally gets around 6 to 7 hours.
It is worth considering if you would like to have something that is small, light and can be used as a tablet. The digital pen allows you to take notes. I am considering purchasing it because with OneNote (free to download) you can use it to record lectures & meetings while writing notes.
Similar to most convertibles with a detachable keyboard this device cannot be upgraded since the unit is sealed. The only way to expand "internal" storage is by using the SD card slot which supports up to a 128GB SD card.