boosters

I think this is one of those questions where there is no "best". Annular boosters are supposed to give you a little better throttle response due to the finer atomization of the fuel coming out of the booster. I have an 850 annular Speed Demon on my 440 and it runs about the same with that carb as it does with a Big's Holley 850 dogleg. Here is an annular vs dogleg comparison that Car Craft did a while back: http://www.carcraft.com/techarticles/116_0508_carburetor_showdown/index.html