I currently have 6 of these in operation. Very steady temperature control (+/- 1 degree per day). Nice look, too. Of the 6, two have stuck on. Unfortunately for my growing fry, I wasn't around to notice one of them. I really do miss the indicator light. My original Visi-Therms lasted well over 10 years with no failures at all. I wish the same could be said for the Stealths. Be careful when sizing your heater, and keep an eye on the temps (always good advice). With an indicator light and some quality control these would be the best heaters on the market.

Very good bang for buck! Grabbed some on sale at DFS and couldn't be more satisfied. Only drawback is that there's no light so you can't see when its on... I've had a couple for a few years without any problems with cold water.

My last visi-therm lasted approx 12 years or so. Much longer than any other I have used over the years. It is now the only heater I will use in the tank.

My Stealth has been going about 2 years now with no problems or temperature fluctuations. I really love how it isn't glass. All the glass heaters I've had ended up caked with minerals and I would have to periodically soak them in LemiShine to get it off. I need the heater in the tank, not soaking in the sink. I wish it had an indicator light on it so I would know when it was on, but my water is always 78 degrees, so it must be working. Like someone else said, the suction cups suck. They don't last and I finally resorted to a cable tie attached to a piece of fake tree root. It works, but it just floats next to the glass. This heater may be more expensive up front, but you save money in the long term since it lasts so long.

I had one in my 55, and it works like a charm, lasted two years, before the ceramic coils cracked one day when I was doing maintenance, I went out and looked for a new one. I went to 3 different stores before I found one. why you ask? because it is that much better than a regular glass heater. I have one in a 55 (With just a Johanni and Auratus, both male), and one in a 30 (Auratus, female). just make sure you select the right size, because it does matter. especially since this heater is so accurate, it could end up over heating you tank. my only gripe is no indicator light. though I suppose just look for the bubbles that form when it's in use. the heater is also a breeze to clean. I just pull it out, and wipe it off with a towel, algae won't stick to that well I find. take it from me, an Aquarist for 8 years now, these heaters are worth the extra $5. they won't let you down.
by the way, I've never run into the electric shock thin with the heaters, but it isn't too much to worry about. in heaters it's voltage that heats the water, and not amperage. heaters tend to have high volts, low amps, and it's amps that will kill, voltage will only make you uncomfortable/cause pain/burn. so long as it's less than .7 Milli-amps (which it probably is) you'll be fine, But I still wouldn't recommend keeping a heater that is shorting out.

I felt a shock when I stuck my finger into the tank. I unplugged one electrical item after another until it stopped shocking me when I put my finger into the tank. The other four Stealth heaters I have are great and I will buy them again when needed

I haven't sent this one 200 watt heater back yet but will, mainly because they need to know they could kill somebody. I had mine plugged into a GFCI circuit which would trip before a real danger to me (and is recommended for all fish tank electrical items). Of course most old houses don't have GFCI installed.

It's a great heater so far...kinda. Theres a huge "bubble problem" - tiny bubbles all over the heater all the time! Even when I try to knock them off they come back. Which makes it not so stealthy. Also, it's just a tiny bit noisy when it clicks on - or is it when it clicks off? There's no indicator light on it so I can't tell which it is. The temp gauge is a little off on mine, about +2, but that was easily taken care of.
Most of all it's consistant. It's always at a nice 78 degrees. So I really can't complain.

I have a 110 Gallon Tank (with lots of Holy Rock so I don't have 110 gallons of water in the tank). Replaced an old regular visitherm 300W that was caked in calcium crust, but still worked fine. I got the 250 Watt and came set to 79 deg. Was within half degree of that after running a day or so. I used a digital meat thermometer on the opposite side of the tank hang down from the lid. I knocked it down a degree and now hangs in the mid 78 degree level. My house stays at around 72 or so, so it only has to raise 6 degrees and does so with no problem. I love the fact that it is black and doesn't screem HEATER! Even though i keep behind a rock, I can still see it when I walk by, but now, not so much.

Just unplug it when changing water and you know it will be out of the water.. do not count in it to turn itself off as it claims..

The Stealth is a wonderful heater if you have jumbo cichlids like I do. they can bang it around and it will take all their abuse. Only downful is once AQ systems was bought out by Marineland they cut cost by using another type of suction cup. I still use my old suction cups on a Visa-therm that are 20y.o. the Stealth's will never last more than a year or so. I just wish they could build a light into it. It would be much easier to check to see if it's still working. mine is accrate to +/- 1 degree

I bought this heater because it's the highest rated and it's inexpensive. It failed after a few months. Alternatives didn't seem better so I bought another. It has a lifetime warranty but for $15 it's not really worth the fuss to track down the address and ship it to the manufacturer for a replacement. Hopefully this one lasts. The thermostat is not accurate but it is quite precise. It maintains the temperature in my 55 gal. tank to within about a half degree. I use the 200W unit. I could do without the bright red knob, but the profile is otherwise unobtrusive. I like that it's not glass--seems more durable.

This is the best heater available on the market. Every aspect of it is superior to any heater I have tried. It is a little expensive, but like in most cases, you get what you pay for. Not to say there aren't any other good heaters, but they don't make one better than this.

Had it for about a year then one day woke up and found the cichlids acting weird. After accidentally skimming the surface of the water I was startled when I received a nice shock. Turns out the tank was energized from the failing heater and I was the ground.

This is an effective heater. It just seems harder to adjust.

Used in each of my four freshwater tanks, had problems with two of them. After 2 years, one failed and two others had temperature dial issues. Almost impossible to adjust by hand, it was so tight. Needed pliers to adjust!