I cannot argue the point of it being more expensive. I believe that's a given. It CAN be a relatively trouble-free system to use IF everything works ok. I guess that is a circuitous way of basically saying that if the mold and slime is not allowed to build up and cause the problems that it does, then yeah. But I'm here to say that I've been on it for 25 years and, while my memory is not as good as it used to be, I think I'm correct in saying that there have been more years where the mold and slime was a problem to varying degrees then years where it wasn't. I'm still 'fighting the good fight', as it were, but not sure how much longer it'll continue. I see a likely conversion back to chlorine next season if a few last-ditch efforts don't help. A big factor is what type of filtering system is used. I have reason to believe that sand filtration is better with biguanide than DE. I have DE. I distinctly recall the pool store people telling me when I switched to biguanide that I will need to work with the filter more. I can live with that, but what I didn't anticipate is the concomitant cloudy water, slimy build up on tiles and walls, rapid filter pressure increase, mold and slime in the filter, etc. that seems to be an unfortunate consequence of the program. The gold standard treatment was the Softswim "Assist" chemical, but that was unfortunately discontinued a few years ago. Then, supposedly CDX was the miracle cure. While it does help maintain the oxidizer level, it does not work to completely prevent the slime/mold issues. While I still DO like the overall biguanide program (odd as that sounds after all I've been saying), it just seems the industry has not come up with something that really solves the mold and slime issues. I'd be interested to know what other products the person steve referred to has used besides the regular baquacil protocol. I say this cause I sincerely do not believe that the line of products they have alone is enough to keep away the biofilm accumulation.