USB Iscsi initiator HBA

Dear Sir/Madam, 

We want to develop an USB Iscsi initiator HBA, but we are new on
Hardware.

We are now seeking for a target board for our production. Seems ATMEL is
a good choice for us as it has many products fit our requirements (USB
FS/HS slave SD card 100/1000Ethernet). 

However we would like to ask: 
1.there are too many vendors/boards and we don't know how to select. Which
board, or even CPU should we focus on? 

2. should we start from the Evalation Kit or simulators like Skyeye? 

thanks and we are apologize in advance if our questions are too silly.

Best Rgds 
Alex Li