Snow Performance has a very good reputation here locally. You see quite a few of their systems up at the drag strip, both on cars and on the tow vehicles, and on the local turbocharged imports.
I have a home built system using shurflo pumps and generic spray nozzles from Mc Master and Carr and now also have an Aquamist system which is another top line WI vendor, that actively supports racing and has bonneville experience. They built the WI system used on the Diesel Max streamliner for example, and build the systems used in most of the WRC rally cars. They have extensive experience with the Subaru due to their WRC experience which is why I chose them for my system.
A third vendor that is active in racing (mostly with the Buick GN folks but now supporting other makes) is SMC.
Each of the vendors have their advantages and disadvantages as far as pricing, features, support etc.
I consider all three of those vendors worth investigating if your interested in building up a system for either a tow vehicle or a race vehicle. They seem to do a good job of taking care of their users.
Larry