Are you Serbian?
I'd have thought they're pretty similar.
I'm not Serbian, but I am very familiar with the league and the Balkan leagues in general, I'm Bosnian. Croatian,Bosnian and Serbian leagues are the same, pretty poor in quality, I've watched enough matches to know that. Crvena Zvezda and perhaps Partizan are on a higher level than the ''top'' teams in Bosnia for instance, and below Dinamo Zagreb, however all in all the league's are generally shite.
the pace of league 1 football is far greater than that any of those mentioned league's above. There is talent no doubt, but you can't compare the English way of football [in terms of pace and physicality] and those leagues.