i think it pays to pay someone to do the head gasket.

A reputable shop who's got insurance. The problem is that if you screw up, you're looking at a lot more money at the end to fix the problem you've created.

If you let the shop do it and they mess up, their insurance will pay to get your things straight again.

I think that's the important part.

But if you have the tools and know how, it would be a nice project at home.

around 13 psi is somewhere where you would want 3mm gasket on your engine.

lowering the compression may save your engine on FI, and 3mm gasket and labor is cheaper than replacing valves, springs, rods, pistons, etc.

that's what I think. because once you had a FI car before, you know you wont leave that boost alone.