While ONE of those IR LEDs isn't very bright, a whole bank of them can be seen from a good 30 or 40 yards away pretty easily. I know, I've done it. Once someone's vision has fully night-adapted those little red glowing LEDs are very very obvious.
Not only that, the lenses on those things are (obviously) very cheap and the image you get is not at true 1x magnification, it's often more like 1.2-1.3x, combine that with the fact that the lens (singular!) itself will be offset from your face by several inches makes walking about pretty hazardous in itself, especially given that with only one objective lens, regardless of the amount of screens inside of it you'll have no stereoscopic depth perception.
Trust me, if those spy goggles were useful on any level then people would be using them all the time, I play a LOT of night games and have only ever seen that kind of stuff a handful of times and in all of those cases the person using them has ditched them in favour of a torch in fairly short order. They're a nice idea, but in practice they're £35 worth which with night vision stuff is effectively 35p worth. You're genuinely better off with a keyring LED torch.