Seems like the 3 top recommended kits for the Bandit are:
(In no particular order)
Ivan's
Holeshot
Factory Pro
I've heard mostly negative about Dynojet and K&N (K&N is actually a Dynojet kit.)
I can't say for sure, but I believe that the Ivan's and Holeshot's jet kits are bought from K&N or Factory, and packaged and sold as thier kit.
I've been told that, but I have never seen thier needles or jets to compare. I have been dragracing for almost 40 years, I have used the Dyna jet kit about 1/2 of that time. We use to say that the Dyna kit was for dragracing, and the Factory kit was for road racing. They are probably all good if installed right.
I have a set of 98 Bandit 1200 carbs with the stage 3 K&N kit, but I have never had them on my bike. I use the 38 mm Mikuni flat slides, and all the new bikes I work on have FI.