I had a not-so-great experience with my Ventech fan, after about 1 year it started getting really really loud, in fact it blew my stealth twice... this was a very serious infraction lol. Luckily, well, nevermind lol. But anyway it got mad loud, like the bearing inside blew out.
This I thought weird since it appeared very sturdy and well made, and plus I had one of the authorised fan speed controllers, and it was almost always about 50% or 60% except on the hottest summer days I'd max it out. But then sometimes it was quiet.. Finally it got so bad, it sounded like a train crashing nonstop lmao. So I emailed VenTech, and yeah of course my warranty was up just a few months prior lol. Just a 1 year warranty??? Geez.
So I just swapped it out for a slightly more expensive Hydrofarm one, one of those big green ones, and it's whisper quiet and has a 5 year warranty woohoo! Honestly I expect any gear like this to last just a couple years, maybe 3. But I was disappointed in the Ventech not barely lasting 1.
Now that's just my one experience, and not saying they're all gonna go like mine. But I wish I'd gotten the Hydrofarm from the jump and wouldn't have to replace one. I use a 6" system which is overkill for my tent but that's why I run it around 50% and it's quiet that way normally. : )