As compared to MPFI ? .. ain't that the truth !! ... but until some company comes out with a system that is straight-forward and reasonably priced - not a whole lot people will be going in that direction.
LOTS of people have talked about this topic on the 'net and the HORROR stories about probs that never can be solved and customer-service from some companies that is an equal horror-show after spending many thousands of dollars.....
I say NO THANKS.
I don't know I managed to get 17mpg in my 340 swinger w/ 3.55's driving around 70-75mph for 30 miles and got 11-12mpg in my S/C'd 440 doing 65-70 w/ 3.91 on a 50 mile trip. Not sure EFI can do much better, and as you state not many "afordable" systems out there, especially if you are over the 350hp mark.
