They're lead which - as I'm sure you all know - is soft. The little "stalks" are also lead. Guess what happens?
Go on - guess.
That's right - they bend. And break.
Guess what else - they're so small that drilling in order to pin and replace the stalks is very difficult.
The sculpts themselves are OK if a bit cartoony, I guess.
Anyway - I'd not long before visited a museum which had a stuffed bat and the one thing that struck me was how not-black bats actually are. Their wings are very like parchment and they seem to be very pinkish - presumably from bloodflow - along the boney parts.
I tried to incorporate some of that into my bats (and Varghulf and other models too).
|1st three bases|
|2nd three bases|