First Time Pool Buyer

I'm new to the site. We're planning to build a pool soon. We've gotten proposals from 4 companies and trying to discern what fact an fiction we're hearing from them. I have two main questions right now:

1. Salt or chlorine tablet or chlorine plus ozone? Three of the four have said chlorine. Two of those included and ozone system. But leaning towards the builder that proposed salt. Who's right about what is the best system?

2. Stamped concrete vs. flagstone vs. "sun" deck or "cool" deck. Leaning towards the builder that proposed combination of stamped concrete and pea gravel. But others have cautioned about "slickness" of stamped concrete.

Thanks!

Don