The Cadillac of feeders, with the pluses and minuses that implies. Pluses: - Powerful enough to work with Tetra Cichlid Sticks which I broke in half (painstakingly, one at a time) to better fit the feeders corkscrew mechanism. This is the only feeder Ive owned that could handle sticks, a crucial consideration for me because I own large South American cichlids (e.g. full grown Severums) that aren't crazy about small flake foods. - flexible: dual feed hoppers which can hold different food(s) and can be individually programmed to deliver 1 to 3 turns of the corkscrew, 1 to 3 times a day - precise: the corkscrews provide the most consistent delivery method Ive seen in any automatic feeder - long battery life: I installed the 4 included Duracell alkalines on or about May 10 2009 and decided to leave it running after my return specifically to test battery life. Its been running on both feed hoppers ever since and as of July 5 2009 the battery indicator still indicates "full". Minuses: - Requires familiarity with the instructions. Plan on spending at least half an hour figuring out the instructions, and at least another half an hour testing it with whatever food you are planning to use, so you can establish an appropriate feeding schedule for your fish. If you are unwilling to take the time, then its not for you. - Every automatic feeder Ive owned tends to clog in the damp basement that is my fish room. Despite a sophisticated design that minimizes exposure to moisture this one still has a hard time with flake foods in this difficult environment, but the sticks worked fine. - The only way Ive found to reprogram the unit is to wipe out the existing program and start over, I don't think you can modify an existing program. A minor annoyance, it isn't a big deal once you've run through the instructions a few times. Note: Its a bulky unit, With a footprint of 4 inches long X 3 inches wide, nearly 5 inches high and with a feeding mechanism that adds about an inch to its length. This is both a plus and a minus. Its big enough to hold quite a bit of food, and its heavy enough to sit solidly on the top of the tank so you don't have to worry about it migrating out of place. Its also tall enough to minimize exposure of the feeding mechanism to tank water. (If this sounds contradictory to what I wrote above under Minuses, its not because I'm distinguishing between exposure to tank water vs. operating in a very humid environment.) The minus is that it takes up quite a bit of space on the top of the tank, so check the measurements before you buy. (I had no problem because I installed it on a 125 gallon tank with glass tops and separate strip lights, so all I had to do was move one of the strip lights.) Summary: I took a chance on this feeder in the hope that it would keep my cichlids alive during a lengthy absence (over 3 weeks) and it came through with flying colors. Pricey but worth it, hence the 5 star rating.