Has anybody got information about the Chieftain for bush ops?
Yes, in a word,
"Don't".
The aircraft was designed around 1 hour sectors with fuel at either end. They will handle bush flying but not as well as the Cessna 402 or 404; they are more difficult to load stretcher patients (narrower fuselage); like lots of AVGAS; are getting depressingly old and difficult to maintain without any real support network in place. At least Cessna will still talk to you and are interested in the 400 series.