Jacob:
I've had both the 40 cron and the CV 40. I found the CV40 at 1.4 to be heavily vignetted. But it will get you that shot if you can't otherwise. Size and build quality are roughly the same. Bokeh is much more pleasant to my eyes on the 40 cron (but this is so subjective). I ended up selling the CV40. I'm not saying bad bokeh, just not as nice as the 40 cron. Test your cron out, and see for yourself. I am guessing you will like it.