Widget Saver – the only chance to save widget config ?

One thing bothers me still – sooner or later you switch between themes with a natural desire to experiment. The sad thing is inevitable loss of widget and some other configuration – I’ve heard that WP 3.5 has sorted it out – is that true ? There’s also a light in the tunnel – Widget Saver Plugin. Is it worth its proud name ?

[Closed as duplicate of: http://wordpress.org/support/topic/the-most-user-friendly-responsive-theme?replies=3 ]