no in one sense, it is usually cheaper and easier to fit a recon/ 2nd hand unit, just a simple in out job plus ecu and wiring
However, if funds are tight overhauling your engine will be better (as long as you got a mate or the experience yourself) as if it goes into the garage the labour bill will outway a 2nd hand. but if you overhaul you can do bit by bit, plus you can save a bit as the head, and all auxillaries may be ok just the block,