Apologies for being a pain, BUT
[really should have added this to the original post, sorry]
I have already taken some time to evaluate the RadChartView, a very promising development.
However, the data we are dealing with very often has null values. The current RadchartView deal with this by displaying the null value as zero. Unfortunately, due to the nature of the data we are plotting a sudden drop to zero is also a valid possibility.
see my related post http://www.telerik.com/community/forums/wpf/charting-kit/lineseries-empty-point-behavoir.aspx
[basically we are plotting instrumentation data, here the instrument may stop working [results in nulls], or may simply have a fault [zero's], or just report zero as a valid value]
EDIT: I am actually very keen to move to the RadChartVIew, the performance difference is amazing. The lack of the ability to show nulls as a gap is pretty much the only thing stopping me.