unless you find a used hondata system for sale the ems is going to be a better bet. with hondata like you said, you need ecu($175), harness ($175){assuming you are not obd1}hondata($495 for s200b only) that's ~$845 not shipped, no options other than boost, and the universal ems is what ~$ 1200 with the works.....
Greddy e-manage seems like you have to buy to many parts and is not as cost effective to add to that, are you planning on tuning this yourself? How many people tune or know how to tune with the E-manage, who has all the accesories? Sure you can do it.....is it worth it?