School me on trans axles, Boxster 6 v Cayman 6 Options

[HalfMoon]

Well, I've decided the time has come to change my sbc powered teener to a better trans axle but in doing some research, I'm not clear on a few things...I've pretty much narrowed it down to either a Boxster or Cayman 6 speed.
While I know there are gads and gads of alternatives many of which the reader will no doubt recommend, for a variety of reason I'd rather we stay on point the original post. And while your guess's are fun to read, first hand experience is far more valuable.

First, I gather the Boxster S and Cayman Six speeds are essentially the same the Cayman having a higher gear set ratio.
True? False?

Renegade Hybrids stated the adapter they make for the Boxster is for the S six speed because their opinion is the five speed isn't robust enough to take the torque developed by a v-8.
True? False?

When it comes to the Boxster and the Cayman five speed, I've heard the Passat five speed is essentially the same but quite a bit less expensive.
True? False?

Would a sbc developing 400hp with something like 350 ft Lbs of torque have the ability to grenade the Boxster/Cayman (or Audi if true) five speed box if driven responsibly with frequent track days?
Yes, no?

And forgive this last question, the Audi FWD 01E trans axle six speed, what models used this trans axle and would it, could it, be used in the above noted spec engine without grenading?

Thank you in advance for your input and first hand experience.