I think you will be happy with any medium or regular plastic.
M-F, Chemionics (Bear), Lurecraft, PolyOne (Del-mart), Ozark Plastics, Calhouns... All have plus and minus to them. Find the one you like and learn how to cook it right.
Everybody will have an opinion on a different plastisol but very few have used all of the types available out there.
Jim