With the Guhl ECU mod I have heard of increased MPG in the improvements that Guhl has done and even with my 1500 I did get some improvement in mileage. If you compare putting in jets in a 1500 you do get some gains and some performance improvements but as a whole its not earth shaking, just a nice little increase or better throttle response. I do have some experience mapping other vehicles and with a normally aspirated engine the gains in power are not that much on the whole, but with a turbo you may be talking some real gains. I have not found anything lacking enough to do something about it on this bike except the things that I have already done. Do I need to map it for the ECU reflash Yes, if you have a Brock’s exhaust you have access to our maps at no charge. I have also never lacked for power really anytime I hit that throttle it has done exactly what I wanted it to do. Considering your Guhl/Brocks ECU street flash for my 2012 ZX-14r. Although some have claimed great results I am just not convinced. I am thinking about it but that may be as far as it ever gets because messing with the computer on my bike that is running well doesn't really thrill me. There is also a Power Commander that will work and has some good reviews. This along with the other things you guys have mentioned. I don't have the cold hesitation but hear that it takes the speed cap off and the fast idle when cold. Please note: Brock’s Performance PCV mapping requires a Brock’s Performance exhaust purchase verification.
The bike should be dyno tested by a reputable tuner/tuning center for max performance and drivability. The site worked fine for me as for the ECU mod I have only seen good reviews. The ECU flash itself will be compatible, but the piggyback fuel maps cannot be 100 correct.