We use this plugin on a multilingual site straight out of the box it had some problems in combination with my template but the support team is supurb. They had it running in no time. I even asked them to make some tweaks to it and they did this for free!
If you are looking for a real one page checkout for VM2, this is the thing!
I recommend it and will use it in all my VM2 shops for sure.
Somehow the way my server was configured did not work perfect for this module. These guys rewrote the code to suit my demands this is what I call support.
Great module ( extension ) and a superb support team! Keep up the good work guys!