guys take a look at OSVR it is cheaper and upgradable with the future improvements... OSVR cost about the half of Vive, ok it has no controller but in visually is far better than DK2 especially the 2.0... on ebay there is some offers for 1.3 and 1.4 with the price that don't reach 250€ and it works fine
yes OSVR 1.3/1.4 (it change only the padding and minor fixes) has an OLED 5.5” Full HD display running @60 FPS... substantially uses a single display which is divided in half... (960 x 1080 per eye) OSVR 2.0 uses dual-display (1080 X 1200 per eye) running @90fps
osvr is open source so it's upgradable without buing every time the newest version but only the piece/s