650 or 750 cfm. carb??

I would personally use the 770 street avenger, this way you get the electric choke that you want and the tuneability that you need. These carbs have very good street manners and great drivability. I would put them against the Eddy's anytime. The 770 would be large enough for your engine at this time and give you what you want. Then later you can tune more to the performance side as your engine get's it's performance mods. 1 carb and inexpensive parts for the up grade later, by parts I mean sec. spring kit, air bleeds, and jets.