Check with your insurance to see what each will cost you. Often their covered under injectable medications and/or specialty pharmacy. Remicade is often given at a hospital and is subject to more costs, higher caps and copays in some policies. Use their specialty pharmacy and it's cheaper (rather than direct billing).
Both have a patient assistance program that helps with copay cost.
Remicade is painless other then a small needle prick when the nurse sets the IV. Humira is a self subcutaneous (just below the skin) injection, a nuse shows you how. It's given in the thigh, belly or other meaty area. Some say it hurts, others not so much. It might depend on whether you have much body fat (flaring makes us loose weight rapidly).