It changes depending on the stage of development. That one point seems to be missed by many. I am currently about 255-260lbs (dieting now but by no means trying to get truly "ripped"). No newbie should be lifting just like me. My training evolved into what I do now. My chest training, for instance, revolves largely around machines lately. Mind you, they are Hammer Strength plate loaded machines (not cable machines), but they are still classified as "machines".
I saw the greatest difference in strength gains (after I hit 405lbs as a max weight on flat bench press) with dumbbells. It also seemed to help me grow better after that point. The only reason I don't do these exclusively now is because the effort to get dumbbells needed to continue stimulating growth into position takes a shit load of effort without a spotter. I would literally tire myself out just getting the weight ready to be lifted. If I had a spotter who was strong enough for me to confide in, I would probably add them back in.
My rating would as:
beginners- flat bench press with the addition of dumbbells for possibly one movement. The rest of the exercises can revolve around the barbell (inclines, declines) as it helps the development of every muscle used to stabilize the weight. It also teaches balance.
Intermediates- a move away from barbells and more of a focus on dumbbells and some "good machines" like Hammer Sttrength thrown in. I began doing the pec deck as a very last movement just to get more blood in the area. I consider it a very poor overall mass exercise.
Beyond intermediate- You do whatever the hell keeps you growing and getting stronger. For me, that includes HS machines laregly as I need no spotter and can continue pushing my limits. My only drawback is that their incline machines only hold 5 plates a side. That isn't bragging, it is simply the truth.