Glen, Welcome to the Forum!
Lots to address in your post.. So this "leading pool company in your area", did you call them up and ask them about chlorination or something? Because they are wrong. First off it is not the salt in a SWG pool that is corrosive. The salinity is just not high enough. Here's the breakdown (I love quoting this)
Your typical SWG pool: 3400 ppm
Your typical tears: 7000 ppm
Your typical ocean: 34000 ppm
Every time we help someone with "corrosion" issues due to their SWG it turns out to be pool chemistry (the pH is too acidic). Or bonding (a component wasn't properly bonded to the grid and created an equipotential imbalance, and it corroded). Or it was shoddy materials that would have fallen apart in any conditions. So if you want to engage in a debate with the "leading pool company in your area" ask them about those issues. Bottom line is SWG's are so easy to maintain, many pool service companies don't like them because the pool owners can do the pool themselves. I have had my SWG since 2005 and I have not had any "corrosion".
You are right the cost of a SWG is roughly the same as the using chlorine over the same time frame.. but it depends on how you calculate that "time". Most people use the length of the warranty as the effective life of a SWG unit... OK, lets do that and figure a 5 yr warranty (some are 3). Then for the sake of argument the break even point comes at 5 years. But what if your SWG cell lasts longer than 5 years? Then any time after that is FREE CHLORINE! My first cell lasted for over 9 years, that is 4+ years of free chlorine! And then, when you replace it, you don't have to replace the whole unit (controller and cell), just the generating cell which is much cheaper. So your break even point for free chlorine is like 2 years. My second cell is in its 7th year, you do the math.
As to ease of maintenance .. they are great! It is NOT a set and forget kind of device, but if properly monitored, its a lot easier than having to haul chlorine and dosing every day or every other day manually. And if you size the unit to your pool properly and manage the other chemical levels like we teach here, its as close to maintenance free as you are going to get. Remember that calculation of a cells ROI in the last paragraph? That doesn't factor in your time. And for me, I can put a dollar amount on my time. If I factor the amount of time I saved managing my pool once a put my SWG, I paid it off in the first year, not five.
So if your PB is happy to put an SWG in for you, take him up on it. Stay in tuned here and we can give you guidance on the type and size of your cell, in fact the whole darn pool design! There is a whole forum on new builds. We love following them from start to finish.
The salt level in pools (3500 - 4500 ppm on average) is negligible and usually not the reason why some areas of the pool have problems. Heaters usually corrode due to the pH being too low. Certain stones are simply softer which has nothing to do with the salt itself. And to make it even more interesting, a non-salt (SWG) pool still has salt in it from the chlorine anyways. 
