For the Moment was a TB, and we can name lots of TBs of the past who dominated the Grand Prix. However, the OP wants more current names. I thought I was stretching a little to include one from 5 years ago.
I heard a neigh. Oh, such a brisk and melodious neigh as that was! My very heart leaped with delight at the sound. --Nathaniel Hawthorne
That's very sweet but as much as I love my girl, I don't think I can say we've had success in the high level GPs. We've just done the smaller National Standard ones - and we might have more success in those if I rode better but thank you for thinking of Nikki!