I can share my personal story - I used to have a similar "mineral system" - The Pool Frog. First year worked great, then things went down hill quickly. I didn't end up on TFP by accident, and I chose my username for a reason.
The Frog worked basically in a similar way to the N2. It uses silver and copper ions, metals, as an algae-inhibitor. They tout the system as being able to "use less chlorine" - but in fact what ends up happening is the pool becomes overstabilized from trichlor use, the "low" levels of chlorine become uneffective (I still ended up with Pink Algae and organic staining on the bottom of my pool) the silver and copper levels can get too high and cause staining, that is difficult if not impossible to remove, the copper turns hair green....the list is endless. My kids hair, their friends hair, my dogs hair...all turned green. I have a permanent stain around the perimeter of my pool from copper.
Once I found TFP and switched to BBB, I never looked back. 2 months into BBB and my problems were over, and I spend less than $12 a month maintaining my pool and I have not had a single issue, and I rarely, if ever shock my pool (even then its for extended vacations or winterizing).
Alternative Sanitizers are nothing but trouble. They are just overpriced expensive gimmicks that reap a huge profit for the Pool Stealers. Avoid it like the plague.
Edit, the article has been restored.