750 Holley vs avs2 650 cfm carb for 340?

Hi looking to upgrade from my carter 1406 600cfm carburetor, looking to gain as much power as I can for the 340, was told different things by different mechanics so wanted to get more opinions, one recomended going straight to the 750 for a noticeable difference not sure if he meant a double pumper or not and the other said the 750 would be too big and I’d be better off with the avs2 650cfm carb. The car sees the street probably 4 days a week and rarely sees the track, either way I want the most bang for my buck to make the most power, what do you all think? Which carb will make me the most power? It’s a 340 with x heads an ld340 intake and hi-po exhaust manifolds with a 3.55 rear