Question for Mechanics: 2200-2500rpm or 2700-3000rpm, what is best???

[Perfectlap]

lower rpm, less lubrication.

Engine is not going to fail because of high rpms. It's going to fail for a slew of other reasons that you can't address while driving.
Those have to be addressed before you get in the car.

[Topless]

Disclaimer: Not a factory certified Porsche mechanic.

I have been wrenching them for many years and have yet to toss a Porsche boxer motor.
I see very little in common with a pushrod V8 so that is probably not the best comparison benchmark. Every motor has a RPM sweet spot depending on engine load where the combination of balance, lubrication, cooling and wear are at their best. My personal choices:

No engine load- 800 RPM idle
Flat, straight highway miles with very low engine load 2-3K RPM
Moderate engine load for passing, hill climbing or canyon carving- 3-5K RPM
Heavy engine load for max performance or motorsport- 4K-redline

I see no reason to ever drive this car below 2k rpm. The motor design is such that it could cause excessive lateral loads especially on the timing chains and IMS bearing. It even feels ugly in that range when leaving from a dead stop. As long as you don't load the engine by passing or climbing I see no problem cruising straight and level at 2.2K rpm. Just downshift to climb hills. A pushrod V8 was designed to cruise at much lower rpm and has no ugly spot in the 1500 range. Apples and oranges.

YMMV