What Kernel is suitable for the following data for SVM classification? I have the following 2 class data, as shown below. . 

Its a hand crafted example using two ellipse equations. I want to know what might be a recommended kernel to be used with this problem if I want to use an SVM based binary classifier.
I think the Rbf (Radial basis function) kernel (Wikipedia for rbf) is the most suited for this problem, as its contour plots are circles.

For instance,  this blog solves very similar problems using the same kernel.