Well in my native country, the Czech Repulic, and many other former communist countries, many of the old guard are now shining anew, as capitalists.
For a good politician changing political sides is no different than it is for a good hockey player changing teams and sporting new colors, IMO.
And as a good hockey player is immediately liked and appreciated by his new fans, so too should a good politician be.
One of the best, Winston Churchill, was like a yo-yo, yet we all admire him.