I can provide some info on my original question. The brush my PB gave me was ****. After a month, bristles started falling out. I was skimming more bristles out of the pool than bugs! There was no way NOT to scratch the plaster with the edges made of metal. But I'm sure it saved the PB a few dollars to give me that junk.
I bought an EndForcer brush, since they seemed to be well built... and I liked the upturned edges and all plastic construction. I got it today, and did my first brushing with it. It was very easy to get the steps and into the corners. It is flexible enough to mold to shallow corners, but stiff enough to get good surface contact. So far so good! I like what I see. Time will tell how it will hold up. I'll let you know in a few months if I see any bristles in the pool and if it is still performing well. I chose the standard white model.