My pool build isn't even complete yet, so I'm obviously not an expert. But..... maybe I can help by sharing my reasons for going with the SWG system.
From what I understand from TFP and my own research, the two different systems (using chlorine bleach and using a salt system to create the chlorine for sanitization) are pretty fairly comparable in costs and effectiveness in making sure the water is chemically safe for swimming.
My reasons for choosing the SWG:
1. I'd never heard of it until I swam all last summer in a friend's pool - about 4-5 times a week. I thought he must have some new form of chlorine (Ha, like there is a way to create a new molecular structure!), because the water felt so nice and silky while in the water.
2. My hair and swimsuit didn't smell of chlorine. **
3. My skin didn't itch and feel exceptionally dry. **
4. I never coughed or had asthma symptoms after swimming there. (always did growing up swimming in "chlorine" pools - just thought it was allergies from something in the grass, etc).
5. Soooo many people claim the SWG system is easier maintenance since you aren't manually adding chlorine on a regular basis. Of course there are others who believe the chlorine system is just as easy.
** From what I've read (not experience), these things won't occur if the water of the chlorine system is properly balanced and maintained. It seems the best way to do that is to follow the methods explained here on TFP (and less expensive, too!)
I guess for the me, the main reasons were for the feel of the water and the hope of a little less maintenance (I'll take all the help I can get).
There are downsides to the SWG system, but those are also debated. I'll let the people with experience on the negatives of a SWGS explain those.
Hope this helps a little! Take care, and again, so glad you're here!! Suz