Just a heads up that this more a tactics thread question than a general discussion one, feel free to ask any more Ork questions you have there or in this Ork specific thread down below:
https://www.dakkadakka.com/dakkaforum/posts/list/9510/767149.page To answer your question, I recently ran a list using the Kanz with the new rules in SoTB, and overall, Kanz actually work better in a Tin 'Eadz detachment than a Grot Mob one. I had the same initial reaction with thinking they could be decked out as shooty, but the overall probelm with giving them Sparkly Bitz is that their shooting output is overall too small and their range is too limited. 6 Rokkit Launcha shots, even with BS3+ rerolling 1's, isn't much in an Ork army, especially when Tankbustas and regular Smasha Gunz do the job a lot better. The walker that seems to make the most of the Sparkly Bitz upgrade is either a Morkanaut in a Dread WAAAGH! specialist detachment (since it can shoot twice) or a unit of 3 Deff Dreadz with Quad KMB.
Kanz are actually much better as a big chunky
CC unit moreso than a shooting one. They have an actual decent number of
CC attacks compared to their shooting (and I highly suggest counting those Buzzsaws as Kan Klawz, the extra strength,
AP and damage all make a huge difference in terms of wounding and making sure you hit hard) given their +1A buff from being in a unit of 3 or more. Moreoever, once you factor the Tin 'Ead buff, hitting on 4's is a major improvement, and makes it so that on average, a full squad of 6 will pump out around 12 hits that are S8,
AP-3 with 3 damage. That can easily wipe out a full intercessor squad or severely damage a tank. Throw in a Warpath buff from a Weirdboy or a WAAAGH! Banner giving them another +1 to hit in
CC and they get even nastier.
If you are to go down the
CC route, so far I've noticed that the Orkymatic Pistons are the best upgrade for them. Giving the unit a 9" base move and reroll advances means they're almost guaranteed a T2 charge. More importantly, it synergizes very strongly with the Deffkilla Wartrike's Advance and Charge aura for vehicles, which could potentially allow you to even get a T1 charge for them if you get first turn. Depending on if you're ballsy enough to try two squads of Kanz, I would say Dirty Gubbinz is a good one for a secondary unit.