Sometimes the same 'generic' cams are sold through various vendors... BUT,
Just the fact two cams have the same lift and 0.050" numbers, does NOT mean they are identical.
One needs to compare ALL their numbers. Most cam catalogs will list the 'advertised' numbers, which are listed differently from company to compant. Comp lists their solids at 0.020" tappet lift, and their hydraulics at 0.006". I don't know what the others use, as most don't say. What most WILL disclose, is their 0.050" and 0.200" lift numbers in their 'lobe specifications' section. The closer these two numbers are, the more aggressive the cam.
Comp has a number of different lobe families for all types... be it hydraulic, solid, or roller. Street lobes are generally less aggressive for longer cam/lifter life, and controllability with 'street' valve spring pressures. They get more aggressive from there. Comp's consistency in listing all their cams' 0.020", 0.050" and 0.200" numbers gives three reference points to judge them from. The closer the 0.020" and 0.050" numbers, the steeper the opening ramps. These cams tend to lift the valve off the seat fairly aggressively. These cams don't have LONG, gentle opening ramps, so their total durations are shorter, and they build good cylinder pressure. You can go to their online catalog (or your own, if you have one) and compare cams with similar 0.050" durations, and you'll see LARGE variations in the 'advertised' (0.020") numbers with cams that have similar 0.050" specs.
Generally, the older grinds will be milder, and have the larger advertised numbers, while the new stuff is a bit more aggressive. For example, their 256 @ 0.050 HIGH RPM solid measures out at 294/256/162, while their 'Max Area' 256 @ 0.050" solid measures 283/256/164
Go to www.compcams.com and click on 'online catalog' and to to the lobe profiles. The solids are around pages 232-240 I believe.
66 mustang real street
302 4-speed 289 heads
10.63 @ 129.3