At the begin I didn't like communism much, because my gold was gone. Workers are fine, after the discover of coal I could build a rail road with a regular worker + a captured workers(which I have a lot). I just research a tech to build tanks, and 90% of my territory are all rail road.
So if you are tech advanced, and have a lot of cities far away, communism is a great Government. Is good to be tech advanced, as you can get the gold (that communism don't give you), from the other civ's.
I had two more tech then other civ by the time I switch to Communism, as I was at war. As I could produce so fast, I destroy those guys in no time, and secure resources, which I made into more gold. So the other civ's were giving me so much gold, that as right now, the best civ are 5 tech's behind me.
When I first got into Communism I tough to myself "I'll just get court houses and police stations in those cities and switch to democracy", but after I get so much gold from the civ's(plus market, banks and the other wonders that give gold, which is all free, because I build the great wonder that pays for), I totally change my mind, and I'll stay in communism.
So to conclude, if you are very behind in tech at that moment, and you don't have to many cities away, communism is not a good choice, but if you are at war, with a lot of cities away from your capital, and aren't so far in tech, communism is a great choice. But you might suffer a little at the begin(in lack of gold).