Update: Fraunhofer IIS codecs aren't freeware or open-source software!
If you really want the best codec-encoder combination, you better try LAME ACM Codec
+ LAME MP3 Encoder
The newer Fraunhofer codecs offer better Variable Bitrate performance, but their output quality is lower than the good old 1.263.
Avoid 'em! Nowadays Fraunhofer is surpassed in both quality and speed by LAME.
When it comes to Variable Bitrate encoding you better forget about Fraunhofer. It's just not on par with LAME.
Not Fraunhofer's latest but without doubt their best encoder to date.