Hey Zak welcome. I would imagine everyone that responds to your question will have a different opinion. Some like ABS, others fiberglass, and others 3D print. All have their pros and cons. As with everything else check out all the suppliers, talk to current and past owners, join a couple FISD and social media groups that discuss these things.
That said I personally prefer ABS. I've built ABS, fiberglass and 3D print.