I installed one a couple years ago after sucking a big gulp during a water crossing, and its more useful on stock-ish H3's. Nowdays I'm sitting 6" over stock on 37" tires, and frankly...I don't have deep water issues anymore. Its more a limb-snagger than anything else. I'm over it. If I hadn't cut a hole in my fender I would have already removed it. FWIW, I also run an AirDoc tube and a Fram (dry-type) paper filter.
Snorkel Fact vs. Myth:
Yes...it works. You can float an H3 in five feet of water. Motor will keep running.
Yes...it does partially block your RH vision.
No...it doesn't add any power.
No...it doesn't add any wind noise.
No...rain & snow don't really have any effect on it.
Yes...by-standers (usually Jeep guys) constantly egg you on, to go "full submarine".