CryptoCrane basically said it all, but I would add GPU rigs in the list like this.

(Best)
AntMiner L3+
AntMiner D3
Nvidia rig(1060/1070/1080Ti)
AMD rig(RX470/570/48/580)
AntMiner S9
(Worst)

The reason I take Nvidia over AMD is that it does better on more algorithms than AMD. AMD is only unfairly good at ethash coins because of its price and power draw. Other than that, it's just like shit.
PS: If you can't get the GPUs at a cheap price, don't even bother.