I would never let someone else fit me to a bike.

There are tons of different fits on a bike and if you spend enough time on one to know you want a custom Ti frame you should know how you want a bike to fit.

IE. I'm a little over 6' and im working on a custom track frame right now with a builder and I knew I wanted a race bike with a lot of saddle to bar drop so I went with a 54 st and a 55 TT.

IE if I should be put on a 58cm bike but I'm not a old man and i want a racier bike so I went with a 56.

I would send the builder specs from bikes you like and your riding now.