Here's a link that compares them - maybe info overkill, but it's something:Acrylic vs. Polycarbonate: a Quantitative and Qualitative Comparison –I think I’ll order an SJMY one. Seems the “starter kit” is the tank and the spare tubes.
Now if only I can figure what is PMMA and acrylic. Oh well.
And there's this from a fasttech forum:
But I got the polycarb, because I like clear and don't use tank cracker juices anyway. And it's what came with my SXK.