I've been toying with this switch for the last little while, since I only ever hit MVPG on AS via the partner miles, never with AS miles. That's largely because I make 3 trips a year to Europe on Delta, and all of my domestic travel tends to be shorter flights along the west coast.

When I looked at switching to Delta the reality is I'd only make gold, and as one of the other posters said, I'd just be slightly above pond scum. I actually have pretty good success getting upgrades on AS, and I have a hard time believing as just a gold on Delta that I'd get any at all.

Plus, the no change fees on AS as MVPG have saved me many, many, times.

Neil