Hi - I've had a SWG for about a year now and really love the feel of the water. As for pros and cons:

First, cons:

- dealing with acid is a pain! As you probably know, a side-effect of using SWG is a steadily rising pH which means you will be regularly adding acid to keep your pH under control. There appear to be some ways to control the pH rise (borates) but I haven't found one that works for me. These days, I add 32 oz of acid every 5 days or so (11k gallon IG). My pH is probably still being affected by my gunite and pebble curing, so might not be as bad a problem for you as it sounds like yours is an already existing pool.

- corrosion/pitting - much of the stories out there of SWG-caused corrosion appears anecdotal and can be explained by other water quality issues, and I haven't noticed any corrosion myself, but it still makes you wonder. I have started to see erosion-type effects under my spa spillway and under my weeping wall, but how do you prove that this isn't just caused by plain old water erosion? I guess the "con" here is that you just don't know, and it will likely continue to nag you each time you see some wearing out of your coping, grout, or mortar.

- the very slight salty taste might take some getting used to.

- additional equipment start-up costs

And, the pros:

- the water feels great on the eyes and skin!

- no need to shock - I've never had any combined chlorine, and I test my water every 2-3 days.

- no need to stock-up on and handle chlorine, although I've never owned a chlorine (non-SWG) pool so I don't know if this is just as much of a pain as storing and handling acid is (which I think is a big pain).

Hope this helps!