Manuel- autos aren't realistic(let off the gas, egine is still in a lower gear at 5000rpm).
I have found new ways to work the manuel. Accelerate into the red line(or just below red line) and, while still on the gas, tap reverse, and it will shift like you have a clutch. This is very usefull on slower turbo cars, as when it shifts with this method, the turbo boost is not lost.
You can also down shift this way, although it is not necesary when not under power.
I've alway driven manuel, although in real life, my car is an auto, but I think that it is better to start with an auto, then when you get good at driving, a manuel is an option.
A Spec racer- by the name i'm guessing you're a Mazda person.....if not, you should know the A-Spec is a Mazda term.