A few dealers hate the Clack, others hate the 5800, others hate Autotrol, and some hate the 7000 and many hate the 2510. It all comes down to personal experience. The 2510 used to break the main retainer all the time. From personal experience, the 5600SXT is a good valve, that is all I can say about it. It has a lot of weak spots, but in general, it is a good valve. I would not recommend it for commercial applications compared to other valves. The 7000 is a commercial duty valve, and it has far fewer problems than the 5600SXT. The number of problems with each is so minimal that we dont even care,. Like the WS1, it has a major problem with the buttons breaking when people take the covers off. But... that being said, it is the way people take the cover off, not just the valve design. The autotrol valve breaks all the time when the top plate is installed. All valves will have their detractors, and some companies, especially the online resellers who dont have the feild experience or sizing considerations that the actual field guys have to deal with will lean toward the simplest solution. When they are making no margins, and living day by day and always behind on their payments, they cant afford to take a phone call to help out the people they sell too. The cost some of these companies are selling the equipment for is ridiculous. The margins are way too low to maintain any kind of service. I try to recommend people buy from local companies, or online sellers that are not bragging about how they are the cheapest. This is one of the reasons why. They will larn one valve, one design, and thats what they will stick with too make their life easier and hopefully eak out a profit. Our best seller is still the old Fleck 5600 electromechanical system. it is more expensive, inefficient, antiquated, and people are simply comfortable with it. It is probably the only valve I never hear people say that they hate. Every valve we sell has some customer somewhere that hates it.
The number of problems with the 7000 are similar to the other valves, it is just that they have had a couple of these problems arise recently. The leak to the brine line, a few bad SXT boards a couple years ago, that can leave people with a bad taste. Fleck on the other hand has been very fast to respond and correct the problems. Compared to other companies, they have greatly exceeded our expectations for correcting issues.
Hope this is helpful.