lirael skins pros and cons

In the years since finding In the Skin of a Lyon, she had learned to make three different Charter-skins. Each had been very carefully selected for its natural advantages. The ice otter was small and lithe, and enabled Lirael to move in narrow ways and across ice and snow with ease. The russet bear was larger, and much stronger, than her natural form, and its thick fur was protection against both cold and harm. The barking owl gave her flight and made darkness no burden, though she had yet to fly outside some of the great chambers of the Library, which were never truly dark.
But the Charter-skins had their disadvantages as well. The ice otter's vision was in shades of grey, its perspective was low to the ground, and it induced a fondness for fish that lasted for days after Lirael shucked the skin. The russet bear's sight was weak, and wearing it made Lirael bad-tempered and gluttonous, also for some time after it was taken off. The barking owl was of little use in full daylight, and after wearing it Lirael would find her eyes watering under the bright lights of the Reading Room. But all in all she was pleased with the Charter-skins and the choices she had made, and proud that she had learned three Charter-skins in less time than In the Skin of a Lyon suggested would be possible.

Lirael, Ch. 20, pg. 179-180