Common sense would say that a suspension designed in the 60's for high profile, narrow, pre-radial tyres could likely be significantly improved with something designed for today tyres and current suspension thinking.
- lower unsprung weight
- better damping characteristics (shock travel longer & more direct as not levered off top arm)
- reduced dynamic loading into the body structure (again a leverage issue)
- contempory caster/camber settings
- option of R&P steering and a brake upgrade
The notion that struts aren't as good as a well designed twin-arm setup is true enough but what's in the early Falcons isn't a well designed setup. The issue of no camber change with body roll when using struts is largely overcome by minimising body roll with sway bars!
Is it worth it? That's up to you.
If it was a choice of reconditioning the original or upgrading to this setup I know what I'd choose.