I've installed 3 of those kits, serviced a bunch more, are they good? Yes and No.
They all require 93 octane or better, all of the ones I've worked on still ping with 101. That is reason enough to stay away.
Also a 2k+ kit is pricey for a kit that leaves you stuck with a pinging 4.2 forever.
Does the kit work well? Easy to install, adds huge pep over a carb and starts every time. Having had a faily good system in your electromotive, this is a step sideways or down.

Personaly I'd never waste one dime on the pinger system, rather I'd do a Howell TBI system.

Here is why.
One day when you see a V8 on the horizon, (maybe not at $3+ a gallon) the Howell computer and harness just needs a couple of tweeks to be fitted on a V8.

Also I like TBI for the trail, just because it is more repair friendly than a MPI system.

SD