If it is new and has been installed professionally then everything should be OK as far as pressures in the portafilter, flowrates etc.
If it is bought second hand though then you will have to check all of this.
I dont own a DT1 although I have used this and the professional Cimbali machines. They all run quite hot but the purge is quite straightforward. You really just purge until it reaches a constant temperature which is something you can see visually. Basically wait until it stops hissing and steaming and settles down.
I think that they are an easy machine to use, the risk is burnt shots if you dont purge them properly.