Ian,
Regardless of the big end being spun, you will still have to do machine work, pistons, rods, rings and service the head. Then you look at turbos so kiss 5k there away by the time you add dumps etc. What about cams that can be another 1500 - 2000 gone right there. And theres the small things like speedflow fittings, braided hose, brackets and fittings that swallow a lot of cash really quickly.