I got a couple of pictures in my album of 85 and 110. I tried taking one at 130+, but I couldn't hold the camera steady for long enough, hence the picture of my jeans.

XF is very stable at 135, but uneven surface makes it difficult to take pictures. Solution - use passenger to take pictures, if you can find a willing participant.

Also, when considering what speed is safe you need to include the weather conditions, the density of traffic, and the location (i.e. in town centres vs motorway or autobahn), capability of the driver etc.. Its interesting to note that the Germans don't have many accidents on their unrestricted motorways, although when they do, they tend to be major.

Incidentally in 1992, I survived losing control (yes my fault) at 100ish spinning car round and somersaulting backwards end over end 3-4 times. Taught me a valuable lesson about mortality and driving carefully (not slowly). And fortunately, only I got injured. I will not be doing that again.