E-manage Blue will definitely bring some gains to your 20v. If no gains, probably there's something wrong with your tuner, the engine or your OEM ECU. However, MT will have better gains compared to AT. On AT, you will have better driveability and it will make your 20V AT more responsive especially on the lower revs. Proper tuning on 20v AT will give you atleast 5whp gain and more if you have proper IHE setup. But then again, I would rather have it tuner for better responsiveness than top end HP for AT.
I'd suggest you to seek an experienced tuner for this and strongly recommend you to look for Ryzzal (as mentioned above).