I'm pretty sure it's been said on here at least a couple times, any aftermarket head, no matter how good they're advertised to be, should be at least checked out by a trusted machinist to check for spring installed heights and pressures, check and church up the valve job if needed, same for the guide clearance, and checked for straightness. I've lost count of the threads I've read on here about people buying heads and bolting them straight on only to take them off within 5-10K miles because the guides are worn out and burning oil, or compression isn't consistent across the board, etc.
Then again, many people never those issues, for them, I'm genuinely happy...what I glean out of their experience is that it only hurts the pocketbook or your schedule once if you bring them to your machinist for a checkup and clean bill of health--even if they are good to go OOTB...if you don't, it can hurt your account worse having to pour more money into buying valves, springs, hardware, etc because something wasn't assembled right the first time around.
also what rocco said...IQ is a busy guy, but he knows heads...
