It's not the most beautiful shrub in the garden, and its holly-like leaves are vicious if you brush against them, but my Mahonia has the merit that it is the only winter-flowering shrub in the garden. It's nice to have a splash of yellow at a time of year when everything is falling off the brass monkeys.
The name, which I always thought was from the first line of a music-hall song ("Mahonia a girl in a golden cage..."), is from a botanist called Mahon, who popularised the shrub from specimens brought back from the Lewis and Clark expedition. It has edible purple berries (the shrub, not the expedition), but I have never seen any wild creature noshing them.
There is no charge for this information. I got it from Wikipedia anyway.