Please Help : ALA dosage?

[BigAndy]

Im confused over the amount of ALA to use, some sources say 300mg a day and others say as much as 1000mg a day. What im really asking is what is the maximum dosage , before an increase will have no added benefit, also how should one consume it, should you spread it out or take it all at once ie what is the max you can take at a single sitting , before an increase will have no added benefit