If you truly trust the machining shop then go for it. Keeping in mind you will always be using higher-octane fuel and if the shop doesn't do it perfetly, you could havea plethora of problems (including, but not limited to, gasxkets not mating correctly causing coolant/oil leaks, un-even compression between cylinders, valves hitting pistons, etc...)

But in theory, it could be done for a decent boost in power. Good luck.