You may want to re-figure your costs.

I figure a 3 month summer, and dumping in a gallon of bleach every other day--about 45 gallons over the course of the summer. Even at $2/gallon, that's $90.

If your SWG costs $900, it will cost the same as 10 years worth of bleach--plus you have to buy sufficient salt and you STILL may need bleach if things go awry. You'll also probably be putting a lot of muriatic acid in your pool--what's that run, $3.50/gallon?--and maybe as much as a gallon per week.

What SWG buys you is CONVENIENCE and effective sanitation at lower chlorine levels, because there's less pogo-ing of FC. You can go away for a week or two and come back to a clean pool. SWGs are a wonderful invention.

But saving money versus the B-B-B method? That's not realistic.