Desktop

Though as both are from Hardly professional I wouldn't expect great performance they simply lack the hardware and enough spec's to tell us what they actually are.

For instance

*16 GB DDR4-2666 SDRAM (1 X 16 GB)

Is 1 RAM Module so it's running in Single Channel Mode which is slower than Dual Channel Mode so it would be better to have 2 X 16 GIG RAM which would be better for performance and your needs.

However saying that depending on how complicated your CAD Drawings are both should be good enough for now to do what you have listed but I would say I wouldn't be looking at any Desktop that I wanted for a few years unless it had at least 32 GIG of RAM and more if possible but then I use High End Systems that require the performance.

I should also add while SSD Drives are fast they simply do not last as long as a Platter Drive so I wouldn't be expecting any SSD Drive to be a long term piece of equipment but a short term bit of kit that will need replacing in a couple of years.

Better to choose the second option and it is support for CAD modelling...