I have a XPS 13 (Kaby Lake), I plan to use this laptop as my daily driver for the next 3-4 years. Hence, I have been wondering possible upgradability through thunderbolt 3. I have looked at different thunderbolt 3 gpu/pci-e enclosures, and they all seem to be priced astronomically. Why is this so? Also will these enclosures come down in price enough to make sense to buy in the next couple years?