Holley Projection any good?

You will get as many advantages of fuel injection as the drawbacks of carburetion will allow. Those drawbacks primarily being the retention of a "wet runner" intake. The projection system is a simple, robust throttle body system. Since you have one, why not give it a shot? If you're not gonna use it, I'll give you my address...

Seriously, I wouldn't expect a huge power increase over a well dialed carb setup, but starting, drivability and economy should be better. Make sure you use best practices with your install and it should be happy.