I've been doing a lot of research on the same...
There's more to Trex than just a law suit. For example:
- it was one of the very first composites to hit the market
- if you ever have problems with Trex that you buy and Trex is ruled against in the suit then what more protection could you ask for
- how long before the other composite manufacturers are sued?
http://www.naturalhandyman.com/iip/infpressrelease/inftrexlawsuit.shtmComposites are just that - composed of wood and plastic so you get a combination of benefits/problems from both. The biggest drawback I've found with all plastic is the amount of expansion/contraction dependent upon temperature and they look like what they are - plastic.
I've found that composite/plasitic options are limited by what's available in my area and asking people what's best is just like asking people what is the best hot tub to buy... the answer is pretty much always the one they sell or bought.