New Build 340/420 Questions

I have been working on this build this year and a couple of weeks ago I broke in the SFT (252/256 109 CL) cam, then I installed the inner valve springs and ran it for another 15 minutes or so and now it has about 45-50 minutes of total run time.

I just completed the cranking compression checks and the lowest was 189psi and the highest was 197psi with an overall average if 192psi. I have 93 octane in it now and plan on using that until I have the tune up close. My first question would be, what are my chances of dropping down to 91 octane (Promaxx/Sidewinder heads)? This is a street build with a 727/3:91 gears/275 rear tires. My initial is currently 24 and I have not checked the total just yet (no VA). I do plan to check it this coming week to see when it is all in.

Break In Oil: I have apx 50 minutes of run time and I am plannning on keeping the WIX oil filter and the break in oil in it for the first few test drives. Then changing out to another WIX filter and Penn Grade oil. Any concerns?

Thanks