Posting what I've said another place:
Okay, well I know a lot of other pros disagree with me, already disagree with flc about this kit, but I think that it is actually quite good, more of a niche weapon than the Heavy Deco, but still quite good. It will probably see slightly higher usage than the vanilla Heavy, but still cannot solo sustain it self as well as the Deco.
I already like the Kelp a lot, and the Kelp is one of my favorite chargers, so this is right up my alley, but can be much more aggressive. I always wanted this kit for another weapon, and I think it works well here. It does not have the same kind of sustain as the invincible special splatlings, but is a similar position to the custom Duel Squelcher. You use your mobility and range to put enemies in bad positions, which is helped by the Wail.
You can dedicate pretty much everything to mobility, probably just run speed, since you do not the special saver/swim speed of a Deco, or the sub saver/ink recovery of the vanilla Heavy. This allows the weapon to be fairly aggressive, and since the wail has such a small charge value, you can afford to be aggressive. Sprinklers can be used in so many ways, as an annoyance, an escape tool, or just to control turf.
These are basic reasons, but I personally really like this kit, I think it is useful on many comps, especially with the inflation of kraken/bubble weapons. It is not great on all maps, but most maps have a good choke point where you can use the wail to maximum effect. I will keep everyone updated on how I feel, but I plan on adding this weapon to my frequently used arsenal, and wreck some noobs in S+ with it!