Originally Posted by Monty
Bisley works fine for me, I wear spectacles and never had a problem with it. Needs to have a slightly bigger gap between the end of the enhancer and your eye than a non spec wearer might choose but there's no contact and it does a good job of blocking out all light. I also have the tube type per Ratinators images on the Daystate so I can use it right handed and the lad can use it left but they're not as good at obscuring light.
EDIT: You need to make sure that whatever you fit doesn't make contact with your spectacles, depending on your prescription strength it can introduce significant parallax error if the angle of the lens changes significantly in relation to your eye if the enhancer is putting any pressure on the lens or the frame and pushing your specs back towards your eye unevenly. If I don't have mine in exactly the right place it can mean an inch or two of extra drop at 55 yards. I can still range accurately but the image shifts relative to the reticule. I don't know if everyone suffers from this problem, but I definitely do.
I don't understand this bit. If you're accurately parallaxed for that range, which you blooming should be if you just ranged it, there won't be any parallax error.
I wear spectacles, and daily disposable contacts are my solution, but have often shot while wearing my gigs e.g. when I've run out, without adjusting the scope maximiser or taking it off.
My experience was entirely different. It is less comfortable as the rubber is touching the lens, and annoying as the oils on the rubber smear your lens (only folks who wear glasses every waking moment can know how annoying this is), but there was zero difference in POI. The only thing I had to be careful of was ranging. I had to change my head position slightly for ranging, to make sure I was looking through the middle of the spectacle lens rather than the corner nearest the nose where the lens is thicker. For shooting I did everything the same