No and to be honest much of any data resulting from 0-60 or quarter-mile is down to the driver skill or surface. The seat-of-the pants dyno said it felt quick at 550 and factory smooth. The fact they have done hundreds of these conversions over the world speaks volumes i.e. it's a known, well researched package and works well.
The 590 is a lot more money for a lot more work on the engine (more than most people know about) and is less easy to justify in extra bhp/extra $.
There are some people on Rennlist and 6Speedonline who have had the 550 conversion done in the US who would have valuable opinions to add. I'm lucky I drove my car to Ruf in Germany and then had lunch with Alois and Estonia Ruf.....
Guy
Guy