It's worth noting that The First Decade does not include C&C3, C&C3: Kane's Wrath, C&C4, Red Alert 3, or Red Alert 3: Uprising. It'd be good to factor those games in when deciding if it's worth the extra money.
I'll happily be taking the download code for the Ult collection, as I've long wanted the entire C&C franchise running entirely off my hard drive. Much thanks OP! ;D