Here is what I see, a board that one solders header pins into that can then be plugged into a solderless breadboard where jumper wires are used to attach it to other interesting peripherals.
To me, this seems like the new preferred way of doing "Arduino" which no longer refers to a hardware standard so much as it is an integrated development environment connected to the device of through USB and programmed in a somewhat C++'ish dialect of a computer language.
Typical curriculum for learning is to use pre-existing "sketches" (programs) with pre-existing board or processor specific "libraries" to implement behaviors from the simple (blink an LED) to the complex.
An alternative curriculum/universe are the mBed boards which are supported by ARM (and are pretty much all ARM based boards rather than a variety of architectures like Arduino currently supports).
So my questions would be what are you trying to learn, and what constitutes "fully featured" in your mind?
In my experience some people use these kinds of setups to learn programming and some use them to learn embedded systems. The the programming aspect typically links together one or more assembled "break out" boards with a perihperal of interest and the programming learning is how to code something that combines that breakout boards library with some behavioral code to achieve some goal. Leaning embedded systems often involves actually building one's own "break out" board and writing the libraries that provide a programming API that can drive that board.
EDIT: As it turns out, the third method that these things are used is with a variant of Python which is nominally "Micropython" (official project), "CircuitPython", the Adafruit variant, or "Ardupy", the Seeed Studio variant.
That makes programming things even simpler. You don't even need any software on your computer (just a terminal program to talk to the board).
So getting this from CrowdSupply with the 'triple shield' and you're good to go.
So knowing what you want to learn, and what your level of investment is, helps give a better answer to the question.