I have not been to Guernsey. But the bank I worked for offered me a job on the Isle od Man. I thought it was a wnderful idea. Accomodation was provided free of charge, a pay rise and a promotion.
I booked a 5 day holiday on the island to see what it was like. After 3 days I was getting cabin fever and could not wait for the ferry to arrive to get me off. It was like stepping back in time.
Before you agree to go, I suggest you go and pay the island a visit for a few days. It may be different for you. But I could not take to it.