Hi i ran since e few month's with the b44.2, therefore the xb4.
Mostly setup sheets of the B44.2 is with in de rear the silver sawybar, or stiffer bar in the rear than the font. In close quick turns it works fine, quick arround the corner. But in long high speed corners, this makes de B44 very instable in de front. you can't puch him through the corner on power or he will tractionroll very soon in front. Befor i drive the Xray xb4, and on high speed with 1.6 front en rear 1.4 mm it was much stable on high grip long corners.
Today i ran front silver an back black en much more stable on high speeds. But even on carpet or astro there is no teamsheet how use this setup. So what are your findings about the swaybar argument.
Lower the car on high grip circuits from 20mm to 17mm will help a lot but not enough.

And yhea in Belgium, BENELUX it's all xray xb4 since this year, but i like the B44.2, but that makes me very 'aso'cial. :-)