Aye, they are a fair size alright (at least 2ft across, you get the clearest idea in the second picture with the nettles just below it).
Doesn't sound like a good eater. Besides, I'd need a wheelbarrow to cart it home!
I've walked past this spot almost daily for about 8 years and never seen them before.
Come to think of it there was a lot of other fungal growths around the area in previous weeks that I've never noticed before.
Are the fungi on the rise