I purchased a composite acoustics guitar for that reason and I love it
I play bluegrass with the valley road band in alexandria AL and so far this guitar has been perfect. You will need to experiment with your string type to find what fits your feel the best, I use ghs meidum strings and they have plenty of tone and bite needed for blugrass. the guitar is the CA GX the strings are GHS TM 335 check it out I think you will be surprised if you are a seasoned guitar player. Also in humid conditions it will out perform any wood.

SC Whiteside