The bigger the better...
Well, in all seriousness, it's a personal choice. The glass tank will weigh more, but at that size it shouldn't be impossible for you to move around.
What is the difference in cost?
Are you afraid of the surface getting scratched?
Afraid of the inside getting scoured by live rock, sand trapped in glass magnet cleaner, etc?
Is the tank "pre" drilled? Acrylic can be drilled later, glass is "iffy".