Jetflite,
My insurance company specifies a requirement for turbine time in helicopters. If they are going to insure you for a helicopter, I would expect all the major insurers to have a similar requirement.
However, depending on the relationship your prospective employer has with the insurer (claims, no claims, length of time, number of aircraft etc), the rules can be negotiated. The insurer will still require you to have a turbine helicopter course but may well accept your experience with turbine engines in general without increasing the employer's premium.
eg. My policy states that I can use any pilot with a medical/commercial rotorcraft endorsement, a total time of 1500 hours rotary, of which 500 must be turbine rotary, of which 100 must be on the same make and model as my aircraft. However, I wanted to hire a pilot that I knew would work well but only had 1200 hours R44. I was given the go ahead from the insurance company to use this named pilot provided I gave hime a 10 hour turbine course.
I had their agreement and everyone was covered. If I did not have a good relationship with the insurer, they would not have entertained the idea.
I hope this helps.
tam