Experiences Audi A8 3.7 Bj. 99

Hello V8-ler!

I am currently driving an Audi V8 D11 4.2 and would like to buy a somewhat more modern car. That's when I got an A8 3.7. Why only a 3.7? I'd like to have a 4.2, but there are currently few Recaro seats, Navi-Plus, electr. Rear blind, PDC front and rear and pre-heating.

Now I have found a 3.7er, which meets my requirements and wanted to obtain from you experiences about the engine/gear unit and possible construction year dependent information. How good is the 3.7 in contrast to the 4.2? Weaknesses/ susceptibility to the engine? Carrot from Bj. 99, are there any problems? What should I necessarily check when buying?

Have you ever had experience of B&B-Tuning's Level 2 performance enhancement? Any idea what they're gonna do about the 320hp?

Performance increase B&B

Would be grateful about many useful information and thank me in advance!

greetings

R.