I was staying at Vallen Nevado and came over to El Colorado for a day. I'm not really a fan of either, but I wouln't reccomend going to El Colorado. Overall its a mountain with slow lifts and lot of very similar runs. When compared to Valle Nevado you just have slower lifts and more similar runs, with very limited big mountain skiing or real difficulty.
On top of the runs being very similar about 70% of the runs were being used for race training and mostly by junior racers from the North America. I used to race and I can see why it would be a good mountain for basic race training. They have wide open faces with good consistent pitch and I saw one face with probably 13 slalom and GS courses set side by side.
That being said no one likes to have their slopes taken away for traning, and certainly not by high schoolers (I do find it kind of cool when your in South America and see an international ski team training).
As is mentioned elsewhere the only really exceptional skiing is on the East side T bar that connects to Vallen Nevado. I will second that this is some pretty awesome terrain ans is the oppisite West side or Valle Nevado. Both these arease are pretty lightly skiied and it finally feels like a big mountain experience.
You can get some pretty interesting lines espescially from the Colorado side if you are willing to ski down to the road and hitch a ride back up. The downside of this face though, is that the T-bar is at some sort of odd angle. South America is full of odd surface lifts, but this was the worst for comfort. Its on a sidehill and puts extreme pressure on your downhill ski. As much as I enjoyed this face, its really have to go up it more than 3 times before you want to give up.
I haven't been to the town or hotels, but have heard good things about price. I did have a good mid-mountain meal that was better than corresponding options at Valle Nevado so that is a plus.
Good to train, maybe good for a beginner low intermediate, not much other reason to visit.