My preference is for T9 premiums due to the economic disadvantage of T9 tech tree ships even with premium camo. Because of that I don't keep any tech tree T9s, just premiums (Jean Bart, Kron, Alaska & Musashi). JB is a great T9 BB with her front only guns and reload booster. If you liked Richelieu, you'll love JB. I don't have Salem, but DM is a great ship especially with the unique upgrade. Salem also has "stubby" radar compared to DM.
Very excited for Georgia to add to the T9 premium fleet. Hope they don't change her before she's available.