Talking about old aircraft, It's seems hard to justify new ones although as pilots we always want shiny and new.
If you look at an old 365N versus a 365N3 or an old 212 vs a 412EP or an old S76A+ vs a S76C++ etc etc etc, there are clearly some performance considerations if operating to Class 1, but not so significant if operating to class 2 (apart from the pilot 'clenched cheeks' factor
to helipad type profiles). A dropped passenger or piece of cargo aside, I would be interested to know how many sectors actually use the full performance profile of the given aircraft. Sometimes there are distinct improvements in the models, but sometimes....
From a financial standpoint, if you consider the significantly higher acquisition and insurance costs of the newer aircraft ($5-6m vs $1.5-2m), versus the presumably higher DOC's (30% or so) and perhaps lower hourly revenue rates of the older aircraft (-30% or so), it seems that the bottom line is more attractive when operating the older aircraft over perhaps a 5 year period - more so for say 600 hrs a year, less so over a 1,000. This might explain why some older aircraft make there way into Africa where the less competitive market and demand for class 1 does not dicate the latest and greatest (and therefore most expensive) aircraft.
At the end of the day I am surprised more companies do not put older series aircraft a la 212 versus 412 etc into some of these markets. Reliability of course is another issue although the difference in the bottom line could buy a helluva lot of spares.
Just my 2 cents worth as I often read about tired old aircraft. Sure they don't have the EFIS fits and all of the latest gadgetry, but with good maintenance they should have a good set of running gear underneath.
Any comments on old versus new would be welcome especially with HAI coming up with all the new toys on show.