318 driver - cam change or not?

I thought I had a decent understanding of cams but the more I look at some of those recommended the more confused I get. The Edelbrock Performer that RRR referenced is 204 at .05 and .42 lift but 270 overall which seems large. The Lunati Voodoo is 208 and 213 at .05 and .454 lift but only 250/256 overall. Yet, when I read a description of both cams they claim to behave similarly. Am I seeing the difference in older slow ramps versus newer fast ramps, and if so, are the newer style cams a lot harder on the valvetrain and seats? Should I just ignore advertised duration and just look at lift and duration at .05? I also looked at the Sealed Power CS1006R and it says 204/204 .42 lift but 278 degrees overall! As near as I can tell, stock 318 cam is 240/248 and .373/.4 lift but can't find numbers at .05. 30 degrees more duration sounds like a lot. What am I missing?