The cutters are 60 bucks. Even if you bought 4 Farrea valves you’d still be under 250 bucks. If that’s your race budget for the year you run on a shoe string.
And the valve job doesn’t know what head it’s going on. It’s amazing that you think they work on W8/9 heads but you’ve never tested anything. So you are trying to convince everyone it’s some secret squirrel ****, but it’s not.