DEM download and speed in terrain correction for GRD product

I am preprocessing some Sentinel-1 products.
Does downloading DEM maps beforehand makes processing faster in terrain correction step? Or is the time change neglible?
I am asking that because I have started processing using Copernicus 30m Global and don’t know how to download it.
Thank you for your help

Automated downloads save human time when everything works. Manual downloads are useful when there are network problems that require retries or even downloading on a different system as you can run command-line downloaders with verbose debugging options to understand and document problems (documentation can be important when you need to generate a support request with your IT people).

Vaov thats a lot of upsides of manual downloading thank you, but I am just interested in speed part. But after checking file sizes it seems there would be no considerable increase in speed. But thank you a lot.