Pounders definitely aren't for everybody.  They are for heavy bikes with one or two cylinders, and sport tourers with very stiffly engineered handlebars.  They stick out more, and on lighter bikes, they may slow down the steering a little bit.  But sometimes extreme measures are called for on a particularly rattly or buzzy bike.  One side effect that some like, is that they tend to act as a stop to make it harder for your hand to slip off the grip.  They also look really sharp.

As you can see in the tech drawing, the Pounders tm weights and throttle locks are 2" long, adding up to a 4" increase in width if your bars are just straight or drag bars.  To the extent that the grips are angled back toward you, the width is less.