That F rating isn't good. I was thinking about giving Mechman a try the next time I am in the market for a HO alternator because he has one that seems to make a decent output for my 2006 Mustang GT.
I should knock on wood when I write this because I just had my stock alternator rewound by a local shop in 2008 and it held up much better than I thought it would. Now that I mentioned that, it will probably burn up the next time I start the car.