The 29-year-old striker has signed a two-year deal at the b2net Stadium, ending a five-year stint with the Valiants, but insists his decision to leave Vale Park remained in the balance until the very last moment.
He told The Sentinel: "I didn't really want to leave, but I have been at Vale for five years and it was a case of now or never. The offer Chesterfield made was too good to turn down.
"It will be very difficult to say goodbye and it brings a lump to my throat to even think about it, but this will be something different, something new, and I'm looking forward to it.
"Vale made an amazing offer to keep me and I had a very difficult conversation with (prospective owner) Keith Ryder just before I signed on Wednesday. It left me choked up because I didn't really want to go.
"I have been here for a long time in football terms and have memories that will live with my all of my life."