The only thing you can really say is a male will reach maximum size quicker than a female. There are plenty of factors involved with how quickly or slowly a tortoise will reach it's personal maximum size. Most have been mentioned
Not really to do with maximum size reached, but some of the last studies of wild horsfields I saw went into when animals became mature in the wild. They figured 7 to 10 years for males and 10 to 14 years for females.
Danny