I just put the stage 1 in my car and I like it. I was told that the reason it doesn't have the emmissions legal certification is that it costs the mfr's money to get that certification and most of 'em don't want to spend it on a part they have no problem selling. I won't have to worry about it til next year, so I wont.
As far as working in a blown application I don't know for sure but I think it will. I think there is an issue with the valve overlap in blown applications.
I have no problems with the piston to valve clearance and I'm running the Edel. 6032's and tfs stage 1.
Good luck with your combo.