A interesting question and answers, thanks fellow Cuties
This is a very good question. And I'm very glad to get the answer!
Thank you for this information, it is good to know and learn something new.
They do lose definition. I had a number of Brother cards, which my dealer converted for me to hus when I bought a Designer, so I could use them on both machines. When out of curiosity I converted them back to pes once I had the software, some of them were too bad to use, especially patterned fills went horribly wrong. You can easily try it out to convince yourself.
When I digitise a design I compile the embroidery design in each format from the design file (which is not an embroidery file, it has the extension .eof in Embird and .can in Viking software) and make necessary corrections in that file. I think most digitisers will do that. In that case is does not matter if you reformat once, but don't do it more than once. So if you can download for instance pes only and you have two machines needing hus or sew, convert them both from the pes - I keep the original and mark it (flower-or.pes) just for that purpose.
Thanks for explaining that. Maybe that is why some of the desisgns mess up for us.