Damm thats nasty.What did the rod bearing on that piston look like?

The exhaust valve looks sunk into the seat to me .Need to ck valve job on that hole, all that alumiun went thru the seat

There is absolutely no reason to change the other pistons unless there is something wrong with them. If all 8 are going to be removed it would be wise to measure them as well as the cylinders to verify the piston-to-wall clearance but you can get a pretty good idea of their condition by closely inspecting the cylinder walls for scuffing, scratching, things of that nature.
While you have the heads off you might want to verify the valve spring installed height. You might find out that, as Strip Poker noticed, the seats are quite low resulting in low spring pressure or needing too many shims to get the pressure up to specs.

They are going to replace 1 piston, rings, all rod bearings and mains, shave head, hand hone 1 clyinder, checked for cracks on heads, clean up valves - claims its ok...for 1200.00
I gave them the block and heads seperate, they will return same way....strippoker, the rod bearing was toast.

Dtile: Who is doing the machine work?

Brocks in tarpons springs,fl Im new to the area.