When using AES, the data size does not have to be divisible by 16, since so-called cipher stealing is used.
Unfortunately, this is only half implemented.
Data smaller than 16 bytes still need this.
So this advantage is cancelled out again.
Binary key and IV cannot be generated simply from strings,
which makes handling more difficult and encourages nasty errors.
The implementation of new base functions shown here in the thread solve this problems.
viewtopic.php?f=12&t=76780