belay glasses

I was at the climbing wall on Thursday, and a geezer was there handing out belay glasses for demonstration purposes. The purpose of the glasses is to allow you to keep your head comfortably level while looking 90 degrees vertically up to see what your climbing partner is doing. The experience was a little weird, but I reckon I could get used to it. The glasses seemed well made and durable. A bit on the bulky side perhaps.
I didn't buy a pair, seventy-five quid being more than I can comfortably drop on an impulse purchase. Maybe I'll just put up with a stiff neck for the time being, but for my reference:
---> www.cubelayglasses.co.uk ++ edit ++ The price is currently £85 on the website