I think it is to hard to tell, but correct me if I am wrong someone, wouldnt a 250A alt be a little to small for a 4500W amp?
It is hard to tell from just an equipment list. I think a 250A is a little on the smaller side, but he does have a decent battery bank to back it up. Also, I tend to trust Singer's opinion, because he's basically the God of Alternators.