Look, I hate to rain on anyones parade, but it usually isn't as simple as just thinking about what cam specs you would like to have. There is a whole lot of science in determining just how much lift you can gain without increasing duration.
The limitation is mostly over metal capability. As you increase lift without increasing duration, the ramps on the cams get steeper and steeper. Eventually (and soooner than later) you hit a point that the forces against the cam face are so strong that the cam either wears out fast or it actually just chunks apart.
Other forces come into effect here too. High revs usually also mean higher spring rates to keep from having valve float (when the lifter no longer follows the cam).
In an attempt to allow for more pressure on the cam face, roller followers are employed, increasing the valve train mass, adding even more to the need for higher spring rates, but having capability for withstanding more pressure.
The pressures on the cam face can be lowered by changing the ramps to increase duration, but the side effect is that the low rpm power drops off (but with potential huge gains at higher rpm).
So it is all a balancing act. Choosing the correct lift to gain power without the need of severly increasing duration, cutting down on low rpm power.
Just where that magic spot is for the Duratec, I really don't know, but I do know that I like the specs of the Cat Cams Stage One cam set. It looks like it may be a reasonable compromise. I would really like to see the specs on the SHO cams.
Specs alone don't fully describe the character of a cam. Some dyno results are usually needed to get a better idea of just how it behaves overall.
