Fiberglass pools

Advantages:

Lower maintenance and chemical costs: The gel coat surface of the fiberglass pool shell is nonporous. This inhibits the growth of algae and reduces the amount of sanitizing chemicals required to maintain the pool. Also reduces the “elbow greese” time needed to keep your pool sparkling clean.
Little or No lifetime cost: 99% of the time there is never any money invested in the shell of fiberglass pools. No vinyl liner to replace and no resurfacing.
Non-abrasive surface: The gel coat surface of fiberglass pools is smooth to the touch.
Built-in Seats and Steps: Most fiberglass pool designs have seating and have steps incorporated into the shell of the pool. More lounging and “hang out areas” in the pool. San Juan even has the popular beach entry models available.
Manufactured in controlled environment: Fiberglass pools are built in the controlled climate of a factory. This results in a much higher quality finished product than vinyl liner.
Quick installation: Because the shells of fiberglass pools are built off site, the installation occurs more rapidly. Our fiberglass pools are typically concrete ready and ready for swimming in as little as four days for most models, but depending on scope of the project, completely finished in two to three weeks on average.
With a fiberglass pool you are purchasing 70% materials and 30% labor.

Disadvantages:

Limited shapes and designs: Because fiberglass pools are built from a mold, the consumer is limited to the shapes and sizes offered by the various fiberglass pool manufacturers.
No wider than 16': Fiberglass Pools are shipped via the road. Shipping restrictions limit the width of the fiberglass pool shell to 16'.
Slightly Higher initial cost: Fiberglass pools are more of an initial investment; usually slightly more than vinyl liner pools but less expensive as compared to concrete pools.

Vinyl Liner Pools

Advantages:

Low initial cost: Vinyl Liner Pools have the lowest initial cost of any of the three types of inground pools.
Customizable shape and size: There are no limitations of the length, width, and depth of Vinyl Liner Pools.
Vinyl liner pools are nonabrasive: The vinyl liner material is smooth to the touch.
Doesn't foster algae: The vinyl material used in vinyl liner pools is also relatively non-porous so it inhibits algae growth.
With a vinyl liner pool you are purchasing 70% labor and 30% materials.

Disadvantages:

Higher lifetime cost: On average a vinyl liner will last between 7 and 15 years at a replacement expense of $3,500-$4,500 plus the cost of water.
Liner warranties pro-rated: Many vinyl liner manufacturers have a 10 to 20 year pro-rated warranty....read the fine print.
Have to use pool with care: Dogs, kids throwing stuff in the pool, tree limbs, etc. are all concerns. The liner is only 20-30 mil thick, which is the thickness of several sheets of paper. One mistake could cost you a whole new liner.
Lower resale value: When you go to sell a home with a vinyl liner pool, many times one of the first questions you will be asked is "how old is the liner?" If it's more than 3-4 years old, there's a significant chance a request will be made to replace the liner before the sale of the house, or the value of the pool will be depreciated.

Advantages:

As big as you want: Concrete pools can be any size, shape, or depth.
More flexibility with design features: Custom Built. Vanishing edges, beach entries, tanning ledges, etc. are all just a sketch away from reality with concrete pools.
Concrete Pools can be integrated into design as a literal work of art in the landscape.

Disadvantages:

High lifetime cost: Concrete pools will need to be renovated every 10-20 years. This involves resurfacing and re-tiling the pool at an expense of $8k-$15k or much higher depending on the size of the pool.
More chemical use: Because the surface of concrete pools is very porous, more chemicals and filtration are required to prevent algae. The alkaline pH of the pool shell also constantly raises the pH of the water, requiring the frequent adding of acid to counteract the effect. Also, many concrete pool companies are hesitant to install salt water systems to their pools, due to the corrosiveness to the concrete.
A lot more maintenance: Concrete pools will need to be frequently broomed or swept with a pool brush to remove algae from the pours of the plaster or aggregate surface. Higher “elbow greese” time required.
Longer install time: Concrete pools take longer to install....usually 3-4 months.