I've got a 2016 ZX10R. I bought it as a change to the BMWs I've been riding for the last 5 years. I've met a few people at track days last year with the new model. All of them praised the handling but slammed the bike as gutless with all the power focussed at the top end. Magazine reviews said pretty much the same thing. This is not really fair. Because of the Euro4 restrictions the standard 10R is fighting with one hand tied behind its back.
When this engine is unrestricted to perform as the original engineers intended it is an absolute beast. If you are disappointed with our bike please don't sell it! After a proper remap and a cat delete it will blow you away. For less than £500 you will transform the bike and be very very happy. By a 'proper remap' I mean one that is able to access the ignition tables and return them to the original engineers' specs. The ignition is heavily retarded in places so using a system that alters the fuelling but not the ignition will result in a very smooth running but still not very powerful bike.
I would say definitely don't bother with other mods before you have a remap and cat delete.