I started on Elitedesk 800 G1s when Raspberry Pis got hard to find and expensive, and I now feel they are better in every respect if you don’t need the GPIO pins.
Every time I open them up to upgrade something I’m impressed with the level of engineering. There are quality manufacturer manuals for them, the cooling is good and they look great
I normally only run one unless I’m doing some dev work, but one G2 plus a 4 bay NAS, a switch, a WAP, and a wireless modem and it sits on 30-55W. This is definitely part of the magic - I assume the i7 6700T is a laptop variant? The other two are i5 6500Ts