It should make a bit more power. No VCT and the smaller AU TB will drop it down a little.
Adjustable gears and some dyno time would be interesting. Or just jump straight into some after market cams.

just out of curiosity what size is the ba throttle body?
i have a 70mm throttle body from back when i had the au engine in my ea (bored out au body)..
good part is , i already have a flash tuner so i can go get it tuned on the au ecu, then later on if i wish to turbo it ill use a bf ecu and loom and still use the same flash tuner..

I'm not going down stairs now to measure it. But previous eyeballing says the BA is noticeably larger.
If you do it, fit the 70mm TB.

I'll just use the AU one, my thing is a gas only ute. I have fitted a non-gas TB and made up a better/larger mixer/intake pipe with a 45mm mixer (stock AU gas is about 38mm). Not much point in a bigger TB for me.
Actually none of the gas stuff is stock anymore, run an OMVL converter with a nissan patrol mixer and gestec processor. the only thing the ECU does is turn on the gas locks and take care of ignition duties.

It's already noticeably faster then a stock factory gas AU. A twin cam with some extractors and pipes should really wake it up.

Any one have any luck ? with locking of the BA cams and EF ECU as I am looking into it currently and would love to be pointed into the right direction please

Thanks