Sorry, but I didn't meant Mr.D, it was someone else, but please take my sincere excuse to bring this back into this thread - my fault.
Coming back to dynos, I guess it's not a matter of dyno itelf. My best friend is running software updates on ecu's and so I am quiet often involved in this matter and of course we run all my cars o see what's going on. My LF1 was measured with nearly 350 HP, as fare as I remember it was 348, so very close to the real figure. In comparision, this dyno shows some few HP less than other dynos nearby.
The biggest issue I saw, was the loss of power during a trackday. This can be measured of course by p-box 100-200 sprint, which I unfortunately didn't checked later.
The comparision of power, I would see as follows. On dyno I expect to have both engines on the same level. On track, I see the power loss more on the V6 side, because charger without cooler will heat up even more, than an naturally aspirated engine.
For me it isn't a big trouble, but this kept me finally away from ordering the new 380. Once Lotus will solve this, cards will be reshuffled.