Just remember, you can only go up. So if they do 1000mg this time, then next time, they'll need 1250mg, and so on. Start low, really low. If you don't get the gains you want, you can always up the dosage next time. If you start out at 250mg and don't gain much, then you'll still be able to go up to 500mg next time and gain more. If you start with 1000mg, you'll get great gains, but you could fuck your system up, and then that 500mg really isn't going to do shit for you. Take it from someone who knows about over doing it. When I decided to up my protein intake, I went from 400g/day to 1000g/day. I spent the next day on the toilet. Then I came to my senses and went to 450g/day, then 475g/day, then 500g/day, and so on. Now I can take in 1000g a day and be okay and make good advances. It takes time to grow, but it's worth it.
BH