Which Trex is Best?
 

One major difference between the brands is whether they can mount on
joists that are 16" on center, or need 12" on center. Trex IIRC
requires 12". I did find one brand locally that used 16", this was
quite important for me since I was using the existing deck structure
(which was 16" O/C). If you are building all new, 12" just adds a few
extra joists which may not be that big a deal.

Most of the rest is up to you, what you want for finish, texture,
colors, etc.