I don't have any experience with any embroidery machine brands except Janome and when I wanted to upgrade, I found it is easier to stay with the brand I was familiar with and that all my designs were compatible with......Janome is Jef and I think Viking is Hus? Anyway, something to think about since converting from one format to another might be problematic or at the least aggravating. Also the learning curve within the same brand may be a bit easier, at least it was for me with my upgrade.
Good luck in your search for a new machine!