I might be opening a can of worm but here is a comparison chart of the "big name" top of the line backpack blowers. Before settling down on a specific model, one must understand that the actual blowing power has much to do with the volume of air displaced (air mass) and the speed at which the blower will move this air (velocity). The blower efficiency index on the chart is a very good indicator of how the blower will perform compared to the others. As you can see here, there is actually not much difference between the three "big names" top of the line blowers (Echo, Redmax and Stihl). You can also see that a good performer not much talked about is the Kawaski KBR750 which has the highest engine power and performs about the same as the Stihl BR-600 while being the quieter of all. On the other hand, the two new Shindaiwa blowers are in a whole different ball park in terms of actual blowing performance with a 33% and 48% increase in performance compared to the much talked about Stihl BR-600.