My home inspection of Speedmaster heads

I remember PHR saying he had to shim two Springs (for the required lift of his customer) and changed out the umbrellas or seals to some better ones that suited him. (I mentioned him by name so anything I miss quoted can be rebutted)
What did you Blue Collar review think of the umbrellas or SEALS or whatever you want to call them?..
they look like magnum head seals to me. Now, how many magnums do you see smoking at stop lights or at start ups after visiting Walmart? Ummmm ... zero. How many LA's do you see smok'n at start up because the valve seals are in the oil pick up tube? LOL.......
As far as shiming, height, yeah, more precise the better. Necessary? Naw. Think mother mopar did this in depth scrutiny to every X head on every 340? Nope! And we love those X-head 340's right from the factory. Again, like I posted early on, I'm not bashing ANY machinist.