Setback will possibly be an issue on most bikes for him. My inseam is similar and I have a BB to saddle of 895mm on 175 cranks. As you go higher on saddles, there is an increase in the distance from the BB that I don't think more 'standard' size riders appreciate. For that reason, the Cervelo may be well worth having a look at. I assume you're talking about getting access to a T4?? Their seatpost is almost vertical and so with his long legs and consequently high saddle he will stay forward compared to other frames. He may need a custom/altered seatpost at his lofty height though. Alternatively you could look at custom frames. I have a custom Duratec personally, fitted for sprint use and it is a rock solid bike