matching bat equipement?

I'm thinking of adding a new pre amp. I own a dc-1, vk200 and ml aerius i. 2yrs ago I auditioned the vk3i w/the vk200 and it sounded unbelievable. A yr later I auditioned the vk50se with the same gear and was not impressed. I'm thinking of either the vk3i or the vk30. Reason I gave the vk30 a thought was do to its additional features. Has anyone ever listed to the 3i or 30 w/the vk200 and was there a difference? Are they the same sounding pre's w/just more options on the vk30? Any help would be great. Thanx Pete