Mike,
I used baq for three years. This will be my fourth year on chlorine (mostly bleach) and I never regret changing. My pool is also 20 x 40 (32,000 gals) and the baq just about broke me trying to keep a clear pool. The third year I never saw the bottom clearly. I can see if a coin is heads or tails in the deep end now and my pool is never a problem. You will enjoy your pool again!!
Best of luck and happy swimming!!!