About fuel management systems: 
 
1) Do Fuel Controllers work? Most definitely, yes.  Today's Federal Regulations mandate
that engines run leaner and leaner over the years to meet or exceed emission standards

that have been set industry-wide.  When properly adjusted they will reduce or eliminate
slow to slow-mid speed surging, provide better throttle response, while also curing most

of the heavy popping (perhaps not "all," but this is perfectly okay) and even slight backfiring
heard when decelerating.  A good fuel controller also, with the slightly added fuel supplied,

gives the engine a little more pulling power most noticeable from mid-range to the upper
end of its power band.   

The downside, which is mostly a non-issue due to the more important "plusses," is that
the gas mileage may decrease by 2-5 MPH as the needed additional fuel is supplied.

Unlike bikes with carbs, many riders of FI bikes continue to ride without a controller and

can get away with it because of the bike's ECU.  Whereas with a carb's bike it becomes
much more critical to re-jet the carb(s) if changes have been made to the exhaust system,

and/or air intake.  Re-jetting in these instances become an almost must. 

To summarize, your bike WILL run better and more efficiently with a fuel controllers, EVEN if you have

included no mods or aftermarket produces, reducing the lean 14.7:1 factory set air/fuel ratio down to

a value in the mid to upper 13's.  And as each mod is added, the importance of the FMS becomes

even more evident.  It doesn't mean that you MUST add the FMS, only that your bike WILL run better

with it.  (not an opinion, but proven and documented facts)