Myself I started with the 3DP11 this a a Prusa i3 compatible 3D Printer and upgraded it to the 3DP12 in the first month.
Finally I purchased a 3DP12 giving me two 3DP12's. Now both the 3DP12's have been upgraded to 3DP17 compatible 3D Printers.

If I have to do it again I would because I learned a massive amount to knowledge during the upgrading processes.
Both 3D Printer I purchased were slightly used, or should I say the owners could not assemble them correctly thous the reason for there sale.
Though I really purchased these because I saw a set of video showing the assemble links below.

https://www.youtube.com/watch?v=O-2d3tjvMPA
https://www.youtube.com/watch?v=Cb_CXRrdv3I
https://www.youtube.com/watch?v=O5S8lFf15UY
https://www.youtube.com/watch?v=jTtfS0-CVl0

Now I said I would do it all over again I would suggest that anyone else may want to start with the 3DP12 or even the 3DP17

My 3D Printers today.

The Twins 2018-3.jpg

I have upgraded these 3D Printers threw most versions of Marlin 1.1.x Currently running Marlin 2.0.X
This is what I used to 3D Print the structural frame supports for my next venture a 3D Printer / CNC

This new 3D CNC is looking good and passed the first Drawing sketch test..
An my latest Assembly V1 Engineering MPCNC Made to my Specs

Any questions Post.