Whats better,grinding a crank or line boring?

I'll be the opposite side of the coin, cutting the block will open up many choices for main bearings, low deck main bearing choice pretty much sucks.

As far as having to fit bearings if you have the mains of the crank cut down, not if the person grinding your crank knows what he is doing. I have a cut down and offset ground Eagle crank in my low deck stroker project and it drops in, no hacking of either the mains or the rods is required, because the person who cut the crank cut it correctly. The reason you have to HACK bearings on the source and some other low dollar cranks is because the money you save over a decent piece like a K1 is saved by pisspoor machining.

Spend a few bucks more and buy a K1 crank , it'll fit out of the box , if it doesn't K1 will stand behind it unlike the other cheap charley, chinese junk, seller .