Bob Motyl KK6KMU
I agree about the critical path. I would like to add geography. Living in a house with a hill blocking my southern direction makes it difficult to hear anything in that direction. And as you suggest without a good antenna system the best rig in the world can't do its thing.
My son-in-laws father just got his K4. It was over a year after he placed his order. He tells me there is a learning curve from his K3.
It all comes down to what you are comfortable with. Have you been to HRO to test drive one. That is if they have any in the store.
Good luck and enjoy,