We are using STM32F4 CPU (at this time we are using STM3240G-EVAL board) with this kind of the software:
FATFS R0.09+ (on SD card)
We try to use FTPD.C and FTPD.H for FTP server, but it has big differences upload/download speeds (350kByte/s and 30kByte/s). We need better dataflow, especially for upload. We try to play with lwipopts.h, but we cannot receive better values.
FTPD is written with LWIP API. We will prefer NETCONN solution. For future we will use CPU board without external RAM -> RAM is limited and we need to set all buffers, stacks, heaps to optimal values.
Please remember that you will NEED TO HAVE AN STM32F4 BOARD WITH ETHERNET ALREADY!
You will also NEED TO CONFIRM EXPERIENCE WITH STM32F4, FreeRTOS and lwIP by reference work or projects!