Yes, I sized up with the trinity. I went with whatever their equivalent of a 6.25 is (I think it’s a 53.) their website says to size down with a trinity, but that didn’t make any sense to me as it would have been wayyyy too snug and would not have allowed for any “play” with the ring. Luckily (or maybe unluckily since temptation is a monster), I only live 10 minutes away from the Cartier store here in Houston and was able to try it on in person so I could get the size right. I think I have a picture of it with my solitaire, too.