The difference is where it's derived from. The general warning you hear about is to avoid things derived from urea because over time it burns the roots of plants so that they do not effectively intake fertilizer, and then the salts build up, and the problem snowballs.

The balanced fert you mentioned should be great for everything, foliage, roots, blooms, etc. You could probably even safely cut it in half, if you're using it with every watering. Overfertilization is easy to do.

Hi Janet,
I agree with the above. I don't like to use fertilizer with Urea in it. Many of the commercial fertilizers have it as one of their components. There are a few which don't contain it: Dyna-Gro, Optimara, and Peters Specialities. I just got a few samples of Volkman fertilizer and questioned them about the urea content which turned out to be 10% which is much too much for me.
Some plants can tolerate it more than others. Currently I am using Optimara which I purchased from Cape Cod Violetry.
Fred in NJ