Lovely looking motor. Don't let the miles put you off... as long as you can establish it has been looked after correctly and not driven into the ground.
I am sure we all know the N54 engine is known for it's (personality) issues, but IMO it's the performance engine that you want - a very special and desirable platform, even more so for tuning. I know for me, all the hardship goes out of the window every time I experience the performance - especially with a remap
Enjoy it, expect things to go wrong quite frequently, and try to get the Mondial warranty if you can. Highly recommended.