I have 2 and love mine. I dont mount them right on my tank. I use a piece of plywood and mount it high so no water gets into the mechanisms. Worked for me now for 3 years
not to be the downer here, but I've never had any luck with them...some lasted a year or two and others even less... motors seizing etc.. , but the most common problem was the lingage inside breaking. I've used the 1/2 and 3/4"models...for me not worth the $ and won't be using them again...I just use different powerheads now.
I have 4 3/4 inch sea swirls. 1 broke after 3 months and they repaired it and has been working fine. The others have been running for over 3 years now flawlessly. I would purchase them again.
I'd say the average lifespan on the linkage within the motor is 5~6 years. I've have ones that are still turning at 9 years and have had ones that needed internals replaced at about 4 years of use.
FWIW, the cost of serving the motor is $75 + your shipping cost.
Used them for a number of years oin my tank, had a problem with one of them say 10 years ago, they fixed it out of warranty pretty cheap. Other than that it's solid.