I'd go for the Spectre EMSPro or Megasquirt. Best buy for the money and lots of FREE help online or from manufacturer. We use and install these units with great success. I use the Spectre EMSPro on my J/FI Turbo coupe and plan on using Spectre unit on my Lt1 Stocker. We are also using one to straighten out shop twin turbo Mustang that was running PMS system with MAF. You can call me if you have any questions 601-371-0815. Spectre unit has builtin 4 bar map sensor, two step circuit, and wide or narrow band O2 sensor capability.
Here is link to company info
http://www.spectreperformance.com/emspro/.