Audi A8 D4 vs BMW 740i - which one to choose?

I'm torn between two of my dream cars and I need your expertise. I've got a budget to splurge on a new luxury sedan and I'm considering the Audi A8 D4 versus the BMW 740i. Both have impressive specs but I want to hear about any differences in performance, features, and overall driving experience from fellow Audi enthusiasts.