I've been doing some web search and amazingly to me i can't find this topic discussed anywhere.

Autocad or Zwcad (at least these two that i know and work with) have the ability to save the drawings by default in a different version than the program. What i mean is that Autocad 2018 by default saves the drawings in AutoCAD2018 format but under options->File and Save one can choose another previous version to save the drawings like.. Autocad version 2000 for example.

I find myself saving my drawings by default in version 2000 because some coworkers use previous autocad programs and many times i send a drawing only to have it returned asking to have it saved in a previous version.

Also i have found by myself than some drawings, specially on newer versions at some point cause strange errors like, refusing to open the plot dialog box, not printing right, huge delays on opening or even failing to just open the drawing, and the best solution i could so far discover is to just open the drawing in Zwcad and have it saved in 2000 version. Nothing else. just a simple open and save as and when i go back to the other program (always autocad that has these kind of problems…) it just gets back to normal and everything works again.

So my question is: Which DWG version do you use by default .. and why?

Thank you.

I always save in the current format I am working in. The only time I worry about this is when I am sharing with external sources. 

I that case I use eTransmit to save to the old version possible.