I hate to interject actual operational experience into a religious debate, but here is my comparison operating a small fleet of light twins hauling freight to semi-improved airstrips. I'm separating out the piston aeroplanes on their own as that is how we kept our metrics..
1991 fleet:
- 2 senecas
- 5 337's
- 9 310's
- 11 aztecs
- fleet dispatch reliability 84%
- 6 full-time maintenance engineers on staff
- 2 pilots with maintenance engineer licences spending more than half time turning wrenches
1993 fleet:
- 2 senecas
- NO 337's
- 11 310's
- 12 aztecs
- fleet dispatch reliability 92%
- 4 full-time maintenance engineers on staff
- 2 pilots with maintenance engineer licences mostly flying
- tonnes hauled up 5% vs 1991
Note that we replaced (5) 337's with (3) conventional twins and hauled more freight with fewer people.
And yes, jhw posting here was one of my 2 pilot/engineers. The kid knows all those airplanes inside and out.