The headset was very easy to adjust to size and not too uncomfortable, I guess it is a case of getting used to the weight distribution, ie: the lamp, the batteries and the lens/s all hang on, or are fitted to the visor and biased very much to the front of the visor. It took maximum adjustment of the grip screws to stop the visor constantly slipping down over my eyes.
I feel a small modification coming on; a rubber washer inserted between the head band and the visor at the grip screws will increase the friction between these two and hence need less aggressive tightening of the grip screws, the present plastic to plastic interface is just too slippery.
As to the set of four plastic lenses supplied, for the price of this Headset, the lenses are surprisingly well made and optically very good. The focal length is a bit too short for my liking, and gets slightly shorter with each stronger lens or combination of lenses used, but that might be down to my wearing spectacles. The focal length is fine for detail work such as model making or jewellery repairs with no obvious distortion or blurring but to me it is not very comfortable for longer spells of book reading.
Incidentally the headset doesn't interfere in any way with wearing spectacles and vice versa. The storage case provided for the lenses is a good idea, keeps them separated and protected against abrasion damage.
The four star rating is given because of a minor intermittent fault with the LED lamp which flickers on and off occasionally. Touch the brim of the visor and the lamp comes on, let go and the lamp goes out. Twist the brim of the visor slightly and the lamp comes on and stays on until the next time you tilt your head or make some other sudden movement........ I guess it's "hunt for the loose connection" time.
Overall, a very good buy and recommended if you are into model making etc.