I am a partner at a landscape architecture design/build firm that specializes in high end ($100,000 - $500,000 & up) custom pools.
Here is my two cents:
1) Gunite is the only option. Fiberglass has a 15-20 year life span & looks cheap, because it is. Vinyl is a step up from fiberglass, but is more widely used in cold climates. Gunite is pneumatically applied concrete that should have a compressive strength around 7,000 psi. A properly built gunite pool will last much longer than you or I will.
2) There is a time & place for all types of commercially available sanitation systems including traditional chlorine, salt water chlorine generator, copper ionization, bio-filtration, etc. A lot of it depends on the materials chosen for coping, tile, decking, etc. For residential pools I typically recommend a Nature 2 (or similar) chlorine tab feeder/ionizer to be used in conjunction with a Delzone Total Eclipse ozone generator with mixing / degassing vessel. You can upgrade your ozone generator to a Pentair Intellizone, but they are much more expensive & are more typically used in commercial applications. I am happy to provide more information on any of these items or how they work if you like.
If you go with salt just remember that it is very corrosive. It will shorten the life span of all of your equipment. It will eat any limestone, cast aluminum, or steel in close proximity. Don't use limestone coping or cast aluminum furniture with a salt water pool. It makes the water feel very soft, but it is not typically the best solution for many residential applications.
3) If you get a spa go with either a separate filtration system (pump, filter, heater) or at the very least use a variable speed pump.
4) Make sure your pool is VGBA compliant. This is a requirement for commercial pools, but should be for residential as well. Ask to see the certification of any suction fitting used in your pool. I recommend Paramount or Waterway.
5) Go with a quartz or hydrazzo interior finish. They wont fade or model over time & wont tear your feet up like pebble.
Hire a reputable builder. Ask a lot of questions. Dont assume that because they have been building pools for a long time that they know what they are doing. Technology in pools has changed dramatically in even the last 10 years. There are many old school builders out there who are still following the same rules of thumb. Ask about water velocities in the suction & return plumbing, ask about the total dynamic head, on vanishing edge systems ask about catch basin sizing. You want to make sure that your builder understands the hydraulics involved in your particular system.
Talk to Brian Brewer out of Memphis. I know he does very good work & would probably be willing to travel to Jackson
http://www.brewerpools.com/