You probably have considered just leaving your cat with a big bowl of food and lots of water when you leave for vacation. Cats seem pretty independent and able to "free feed" and use a litter box when needed.
Only a pet parent knows for sure but studies show that cats really do need us. Hiring a pet sitter will ensure your cat has some supervision and companionship while it stays in its accustomed environment. Most pet sitters recommend at least one daily visit for a cat. They will scoop the litter box and provide fresh food and water (which is healthiest for your cat.) Most importantly, a pet sitter will monitor your cat's health which can deteriorate suddenly.
24 hours can be critical to a pet's survival.
Also, if your cat requires medication, you can hire a pet sitter that can administer the meds as prescribed.
Some cats are not good "free feeders" and they will eat too much if it's available. You can purchase mechanical devices that will deliver measured amounts of food over specific intervals to prevent gorging. I wish I had a $1 for every yucky watering tank I've seen. They get dirty fast.
Kennels can be highly stressful for your pet. There are cat-only boarding facilities that are less noisy and more suitable for your furry friend but the chance that your pet with contract a communicable disease is greater when exposed to other felines. You can ask a trusted friend, family member, or neighbor for assistance but many people feel uncomfortable asking for such a huge "favor".
They key is finding the right option for you and your companion without risking his health.
To find a local professional sitter, consider contacting Pet Sitters International (336-983-9222). They have a tool which allows you to search by zipcode. PSI requires that their pet sitters be insured and bonded. Many of their sitters will also submit to background checks and have passed a certification course for pet sitting that includes first aid techniques. Any "extra" credentials will be noted on their listing with PSI.