LA 360 - 0.030" Undersize Main Bearing Clearance Questions
I'm no expert, but if you have doubts, and it sounds like you have lots of doubt, I would probably go with option #2 for both peace of mind and to prevent significant additional costs if it decides to take a dump on you in short order, plus what better time to go with a stroker crank for some extra cubes? If your machinist is confident that it can be ground and correct bearings can be sourced, ok.
For me, I don't want to do it twice and can't afford to anyway.