New to list, need gearbox info

[Mark Todd <marktodd@internet8.net>]

Audi fans,

Without starting a flame war re: torsen diffs, I'd like
to gather the following information:

- How does a car with torsen center and rear behave in
an autocross environment?  Experience only, please.

- By contrast, how does a car with a locked open center
diff handle in the same situation?

- How much horsepower can the torsen-equipped gearbox handle?

- How much could I expect to pay for a good one?

Many thanks,
Mark