top tip: fiddle with the glasses
the glasses are 80p, they are NOT high quality bits of kit, and while they still work, they can be improved greatly by moving them around.
for example, tilting the glasses forward, brings the "vanes" of the horizontal polarisation closer together.
i spent the "lovey duvey" bits of the film, fiddling with the glasses while watching. (putting them on upside down turns the 3Dness inside out)
ANYHOO, i found the best position for MY glasses, was tilted forward, with the ear-arms clamped about an inch above where they should be, and rotated left slightly, as we were sitting on the left side)
did seem to make a fair difference to me (though i may have been imagining it)
not the strongest film out there, but i liked the "hardware" bits (guns and helicopters) and also loved the creature design 🙂