Hi!
I'am very interested in this topic but unfortunately I can't speak your language:) I hope I can talk to someone...
I read:) that you have tested not only the machines but the new vrays (1.48.03, 1.50.06) also and you noticed speed improovements... It is the same by me: 1.48.03 is 10-20% faster than 1.47.03! That's great but there are some quality issues! The images are almost the same but look at theme carefully! The 1.48.03 differs: irradinace map looks awfull at some places, the reflection are a bit wierd and the most important, it is darker! Mostly in interioir scenes darker images computes faster and my experinece is that the hardest thing is to get more light in the darker areas....
Other words: when you want to get similar brightness the 1.48.03 is not faster but slower than 1.47.03, not menthioning that I get awful GI when I tried to increase the light. Some images would be greate... but I don't have right now...
Ohh and my results (1.47.03):
3800+ x2, 2gb, 2000mhz -> 6,45min
3800+ x2, 2gb, 2500mhz -> 5,30min