I'd say it depends on how much you expect to fly with Delta next year. Silver Medallion isn't much, don't count on a lot of upgrades, but it's better than nothing. I'd put up with a few hours of less comfort with Alitalia to get that. Their business (Magnifica) class isn't that bad. If you like red wines, the last time I was in it (BOS-FCO-BOS) they served a very nice Montepulciano.