This is something that is fascinating to me. Looking at the photos on the Lomography site, the images have that central sharp look, with softly blurred backgrounds and corners that is reminiscent of the images of the past. The pictures that Fenton took during the Crimean War, for example, have this feel.
The swirly bokeh of the Petzval lens makes me nauseous, and turns me off. But, this doublet is certainly intriguing. The bokeh is very natural and beautiful with this lens.