I must say that teardown pictures totally changed my mind. At first I was decided on maxed out 21". The base price in my country is 7000 PLN. Fusion and RAM upgrade bumps this to 9069 PLN (29%). Those two updates are crucial to make machine future-proof. I'm not a data hoarder and 256 GB are more than enough for me, so I can buy Vertex 4 for about 850 PLN. Which will have 50% less failure chance than Fusion Drive. And will be totally silent. When it comes to RAM base version has 2x4GB so both slots have to be replaced. 2 x 8GB Corsair Apple Qualified costs 300 PLN. So manually upgraded machine costs is bumped to 8160 PLN (16%). And removed hardware can be sold dropping whole upgrade bump to about 10% of base price. Even with included suction cups price (hey, you can play spiderman after upgrade using them ) this manual upgrade became my favorite option.