I got into ag a few years ago and fly fixed wing and rotor. There are a lot of myths out there and you will need to do your homework before committing to it. Check with Eagle Vista in Florida, they have free videos on youtube that will give you an idea of what it takes.
You will hear from people that you will have to work the ground for a couple seasons, fly a piston for a couple seasons, spray only fungicide/insecticide for a couple seasons, etc. In my experience, that is not the case. It more depends on the operator and your attitude/personality. Operators with good track records and good relationships with their insurance brokers are getting guys straight out off flight schools into turbines. Find an operator that wants to mentor you in, you will be better for it.
If you are serious about it, attend the National Agriculture Aviation Association convention in Reno NV this December. They have sessions designed for guys just like yourself where operators will be answering questions and making connections. The top Ag schools will be there answering questions as well.
This business is about networking and making connections, go meet some pilots and operators in your area. I will fly for 4 operators this year and every one of them was a word of mouth connection, not answering an ad or them seeing my resume.
Good luck