First impressions is W O W
The power delivery is impressive. It has a real turbo kick from about 1,000rpm, so there is next to no lag. The poser delivery is powerfull then tapers off as you would expect fafter 4,000rpm. While the car has get up and go, I found just chuging along is much better. It just is a relaxing car to drive.
It has a diesel noise for about 1/2 a second from take off, then it has a nice v6 sound. I can see why this car would do a 0-100 in 8.2, it felt not much slower than the TTG, just not as brutal.
I think the transmission badly let's this engine down. Kicking back down a gear to pass or accelerate there is a serious delay in the transmission, which combined with the normal diesel lag all results in a lot of waiting. My co pilot was would tap the steering wheel when putting the foot down and we would count a good 3 to 4 seconds until we could feel the strength of the turbo build. Driving the v8 directly afterward was different experience. While the transmission response was no better, the engine still more responsive or put another way, the power felt more usable across a broader spectrum.
The fact that the turbo diesel does not have a sports mode that holds the rpm and turbo pressure in the sweet spot is probably what I was missing and was the deal breaker for me. It simply took too long to get to that sweet spot and when moving to the next gear had to start all over again. I love turbo charged engines, had 7 of them now, but I'm very fussy about their power delivery in combination with transmission performance.
I have to say I test drove a diesel back in June (car was so new they had to literally tear the plastic off the seats for me). I did this just after driving he 5.7 and was so impressed with the diesel I ordered one on the spot. I currently have a Range Rover Sport 2.7 diesel and though I only had a short 15 minute drive, when I got back in the RR the engine felt old and underpowered compared to the Jeep.