IMO there is no best kit. They all have short comings. Depending on how much you need to inject the little shurflo pumps that the big injection companies use may not be strong enough to give you the proper atomization.
I'd say to "do it right". You'd want the top of the line cooling mist, labonte motorsports or possibly even a snow performance kit. And substitute the shurflo pumps with a real pump. Probably need to upgrade more components at that point.
Snow looks like it would be the easiest to adjust.
Labonte's new S4 looks like it would give you the best ability to dial it in.
Cooling mist looks like a
PITA to adjust, but they offer a stand alone controller that will let you control when other things come on like nitrous.
You just have to do your research.
I personally have an Alcohol Injection Systems kit minus the controller. I picked up a progressive boost controller from labonte.
If I had the dough and could do it over I would go with a labonte or cooling mist controller that used boost & egt to activate my pump. I'd have solenoids for each nozzle and possibly separate pumps.
Another one to look at is Devils Own. They have pretty good pricing and a decent controller.