Great razor. Mild compared to other SE's, but gives as good a shave as just about any DE I have tried. It is easy to load, and it is easy to find the right angle. The PB was the first SE razor I tried, and it is still one of my favorite razors to use.
The head geometry is very similar to that of the G-bar, so the shave should be pretty similar in terms of aggressiveness. I prefer it to the Feather Weight, better balance.
Starting with the G-Bar/Heavy Flat Top, maybe even the Micromatic Flying Wing, right on through the Contour II the frames are basically the same. The only real difference is in the handles, and how you open and close them. When I tested the adjustable Gem the difference between the lowest and highest setting was quite apparent. Most guys will say that they are much milder than the early models.
If you don't already have an SE razor, the push button is a good choice. It gives a milder shave than most of the all-metal GEM razors, like the Flying Wing, Open Comb Micromatic, and Clog-Pruf. I had one for a while but sold it because it was too mild for me.