I'm looking for a preamp to go with Emotiva XPA-2

I recently upgraded my amp to an Emotiva XPA_2, along with an OPPO BDP-83SE. I was informed that my Denon 3808 receiver would not do justice to the 2 channel Oppo. I borrowed a 'Little Dot' headphone amp and was blown away by the vast improvement over the Denon. I also tried the Emotiva USP-1 which was good for it's price, but I very much preferred the Little Dot preamp...too bad it doesn't have HTB. So I am wanting a preamp with HTB. I've been looking at either a Belles 21A, a VTL TL2.5, Placette Line Stage, Juicy Peach/Blueberry or an Adcom GFP-750. Any thoughts to how these would work with my Emotiva/Oppos setup. I should add that I'm using Polk LSI9s for the front. Any good advice would be appreciated.