Reef Monkey,
I really liked the scwd whn I first got it. It was cheap, VERY energy efficent, and added no heat to the water. My water conditions were not that great, so I had some algae growing in the tank which clogged the scwd a few times when it got sucked in the return. One time, my alk got out of control, and I had a bit of a snowstorm in the tank, and the scwd clogged. Another time, the scwd got louder and louder, then silent, and i noticed the door inside had some crap under it that caused it to go a bit off balance and screw the base into the 'door' and break the plastic. I glued it back together, but the door never was fully strong, it kept breaking.
I
modded the crap out of my scwd, and had a lot less issues (especially since I got water quality in line) because I was able to clean it easily with a cleanout adapter, and re-glue the door that broke, eventually using zip ties to get it to stay together. I even added a 3/4 adapter to the bottom and drilled out the top outlets for more flow.
I dont use a sqwd any more, because I got tired of fixing the damn door, and cleaning the thing out every few weeks. I ended up getting the
OM 2 way squirt which I am IN LOVE with. It had a lot of microbubbles at first, but I am addressing those issues. Also the motor gets hot, but I cant see any real increase in water temp due to that (the motor is out of the water). This is an expensive option, but saves me a lot of time during water change day from cleaning the scwd, and this this is not going to have the same problems the scwd's pinwheel and revolving door will have.
I say depending on what you are looking for, the scwd is a fine choice, but has its own kind of maintenance like any other piece of equipment out there. There are other options with less maintenance, but you always pay for conveinance.