Here is some general info that we know about each of them:
Vedral - Sophomore - 5.3 2-star recruit w/ no P5 offers, knows the playbook inside and out, great teammate helping the others get up to speed, looked very sharp in mop-up duty last year at UCF
Martinez - Freshman - 5.9 4-star recruit, excelled in a similar style offense in high school, missed all last season with an injury, seen as the perfect fit for the offense in the future
Gebbia - RS Freshman - 5.9 4-star recruit, 2nd ranked passer in California high school history, came in as a pro-style QB but known for his insane work ethic, impressed quite a bit in last year's spring game with sharp quick passes and some surprising runs
Honestly there isn't much to go off of with any of them yet. I agree we shouldn't discount Vedral's experience but I also don't think we can discount the fact that Martinez and Gebbia were seen as players with MUCH higher ceilings coming out of high school. It seems like Vedral has outplayed his 2-star billing so far, but Martinez and Gebbia certainly haven't done anything to sink below their 4-star expectations. I just don't know how anybody can project Vedral to overtake them at this early of a point in all of their careers.
The good news is I think we all feel comfortable with this staff's decision-making and the battle is going to be really fun to watch.