Hi there. I am attending the program at the moment and I can say that the quality is pretty decent. You have 8 Serbian and 8 French professors. So far we only had one French professor, who was ok, and the rest were Serbian, which to my surprise were very good. Since I presume you are an expat or a foreigner, not sure how would this work for you as all the Serbian professors teach in Serbian, so you have to know Serbian. As far as business connections go, this is not your typical US/EU MBA where the most important thing is to network; you do get to meet very interesting people here (the selection criteria is pretty tough)
Bottom line, I don't think that the program is the same level as HEC in Paris, however you can't beat the price (let's face it, in the US, you'd get 1-2 classes in a third degree institution for this money), and ultimately you do get the same degree as you would in Paris... My personal opinion is that 99% of the business schools are the same thing as this, and that it is the piece of paper that will help you once you graduate, not really what you have learned...
Hope this helps and good luck