I gave speedmaster 3 chances with other parts and all of them had major issues with quality or design. So with speedmaster I assumed I would have to treat a set of heads from them as cores out of the box... With that I chose Edelbrocks where there is a chance they might work with some minor adjustments and customer service in the US to talk to.
Thanks for the heads up. I'll have to double check the guides. I have only pulled the valves on one cylinder to look at the port. The stem seals are pretty tight so I can see a tight guide and low oiling causing a valve to scuff pretty quickly.
If anyone has tips on porting the RPM heads, I'm looking at that next.