In a vacuum the Vega is strictly a better mining card. In a head to head comparison I'd always take the Vega. You should take into account that they can be a pain to configure and users here have reported several issues with crashes. If you're willing to do the extra work you'll get better rewards from Vega.
This thing of crashes on Vega really scary me. I've just read 10-15 posts on google.. It would be nice to know more about some Vega users.. Does everyone have problems?