So, I have to know........ (solid vs hyd)

In terms of customers... Most want the power, they also don't want the noise. I've had noise compaints from the natural sounds of the lifters, especially with the thin, sound-projecting MP cast covers. I've even had complaints about the clips on the locking header bolts making noise. The other issues are cost and need. But primarilly it's noise that bugs them. I prefer solids myself, more because I can get more torque, a better idle, and better overall performance from them. But like you hear from the Grinch - "Oh the noise, noise NOISE!!!" It's hard to explain it's normal and acceptible, regardless of power level. So that's why I recommend them a lot.