All I can gather from his post is that the B44 battery tray is stronger!
I know that the Tamiya wishbones are about the toughest out there. A while back there was a thread detailing the modifications needed to fit them to a BJ4. As for the bulkheads, well the AE ones are plastic and the Tamiya ones are aluminum. The rear arm braces are plastic on the B44 and aluminum on the Tamiya. The AE top plates are about the weakest of any 4wd car I have seen. Not stacking up too well so far for the AE! If the Tamiya is a tank, why would you put the AE parts on it?
As for the Durga vs Lazer SP question, I think it is fair to say that the Kyosho is good to race straight away (with the addition of electrics!) but the Durga requires someone who is a Tamiya enthusiast to put in the required effort to get it to race spec. Out of the box, the car is going to get eaten alive by a similarly talented driver with a Kyosho or an AE. I think Ashley might be trying to wind Roger up!