How should I send incentives to builders?

Originally I started using coinbase transfers in my executor contracts. So I am assuming in this day and age, that the ETH is sent to the validator when using that. But I noticed that a lot of the builders provide a fee recipient address - I am guessing that is their address, and they forward funds as they see fit to the validator. So here are my questions:

  1. If I use a coinbase transfer as my tip, does that mean the builder does not get any of it?

  2. If I am sending the bundles directly to the builder, should I send ETH to their fee recipient address in the executor instead of coinbase?

  3. If I am sending the bundle to a network (such as BloxRoute) that forwards the bundle to many builders, I will need to use the coinbase transfer in that case. In this situation am I better off including my tip in prioirity fee? (I guess that would still only tip the validator?)