a while ago they were doing fixed power 10x50's for £14.99 that for the money where not bad but zoom binoculars are at any price a waste of money.
you get very narrow field of view, hazy image, poor optical alignment giving double image and or head aches, very dim image at any where near full power and fall apart plastic build quality.
i've bought and used or at least sampled 100's of binoculars(i collect binoculars... well just the good ones)
if you want good quality build, optics and realistic power for a hand held use with a sharp clear bright image go on the bay and pick up a pair of old "made in USSR" (not the new russian federation ones) bnu5 8x30's for around £25 or cheaper.
i've never ever found a good pair of zoom binoculars.