Nah, it's all relative. Start late, practice hard. Start early, practice hard. Depends on your background and how much effort you put into it. I think I remember seeing something about clapton spending only 3 years on gutiar before hitting the lights. I've got a **** load of musical experience from my musical parents other than guitar from too early to remember but I started guitar when I was 14, 10 years ago. I've changed complete playing styles 3 seperate times though which has its advantages and disadvantages.