Any motor made needs a roller cam because only roller cams can survive for long with today's motor oil. Support for flat cams disappeared Dec 20, 1999 when the last drop of motor oil was made with the full compliment of ZDDP chemical additive in the oil that a flat tappet requires. Current ZDDP levels with a high mile greatest level of sacrificial
metal is only 40% of what was in SAE 30 motor oil graded as SE/CD back in 1968.
Edelbrock makes the castings that GM Performance Parts sells in their catalog and puts upon their crate engines. They differ from a standard Edelbrock head and why they don't say Edelbrock on the end instead being marked as GMPP Signature Series heads because they use larger diameter valves and are partially CNC gasket matched and pocket ported. Crane Cams makes al of the roller rockers for GMPP and the valve springs and keepers as well as the being the source for the roller lifters used in the engines though Crane actually buys their roller lifters from Morrel. I mention GMPP because Chevrolet engineers specified these parts as being reliable enough to offer them with a full GM one year warranty as if it were installed in a new car (when these parts are bolted on a new GMPP crate engine.
Edelbrock is in the middle of the road in terms of a performance brand, but is best known for delivering
the best bang for the buck (not the most horsepower available, but the most horsepower per dollar). They have a very nice system of top end kits that are listed by the amount of horsepower you want to make per cube of engine size for a SBC which is the industry standard for gauging horsepower per dollar.
A SBC makes an economical (that is a relative term not absolute) one and a half horsepower per cube. Put the same level of effort (parts and pieces) into a big block and you are lucky to see one horse per cube. this difference is a function of the difference in the design of the two engines. You can easily obtain two and a half horsepower per cube with a SBC just that you are going to pay through the nose for it and the engine will be an all out race engine unsuitable for street driving. You can easily exceed any amount of power that a SBC can make with a big block by simply building a larger displacement big block (they can be made as large as 907 cubic inches today just not economically).
This all assumes normally aspirated, as adding a power adder such as NOS or a blower just ups the amount of power that any engine can make equally across the board so there is no advantage given one engine over another. In terms of competition with a door slammer the state of the art is a Pro Stock car that makes roughly 2,400 horsepower limited to a maximum of five hundred cubic inches. The current winningist car is a big block Chevy (actually one through seven of the top ten are BBC with the others being Hemi powered). These are exotic and expensive and illustrate that unlimited horsepower isn't enough as the winner is determined by who gets their horsepower to the ground the best with limited traction (chassis and clutch tune) not the most power on a dyno.
Here on this page of Edelbrock's web site you can pick (butget) just how fast you want to go. It lists the horsepower range per cubic inch of displacement for the five levels of Edelbrock power. The base is a totally stock head and intake that replaces a stock cast iron one. it offers no performance gain over stock other than being lighter than the cast iron parts it replaces. The top is Edelbrocks idea of flat out competition which as I pointed out isn't going to win you many races as there are products available that will make more power, you just will pay a lot more for it.