NO KITS!!
Gringo Josh--A big +1 on the previous comments. You get what YOU need, not what the kit maker wants to sell you.
Coated 1-piece appropriate size cleaning rod is a Good Thing. The other posters have named the other stuff you actually NEED to clean guns.
Suggest that you make a case for the cleaning rod--A length of PVC pipe works great--put a cap at one end, and a screw-off cap at the other, and Voila! cheap protection for an expensive and rather fragile item.
I DO like the pull-through cleaning thingies--But not the ones with steel wire; get the nylon rope variety. They work nice for quickie cleaning @ the range. Agree that they are no substitute for a "real" cleaning.
I'd add a supply of rags for mopping up the inevitable drips of "extra" solvent and oil. All-cotton T-shirts are good; so are worn-out all-cotton washcloths. Those red "shop rags" that you see in auto repair places and such, are also very good, if you can find a source w/o paying rent for the rags.
For patches I buy shotgun sized patches, and cut them to the needed size with a pr of scissors. No need to buy an assortment of patch sizes. Get WOVEN, not knit patches, as the knit ones stretch and can pull off the cleaning jag.
For oil, I bought an $8 bottle of Mobil 1. Expensive for car oil, but a lifetime supply of very high-quality gun oil at a cheap price, compared to the cost of the little 4-oz. bottles. I dispense it from an oil can with an internal pump and a long snoot, obtainable @ most hardware stores.
For cleaning I have Sweets, Outers, a couple others that followed me home from here & there, and 2-3 cans of the foaming bore cleaner. For really tough jobs I have an abrasive cleaning paste, but haven't needed it since I bought it.
@ a gun sho I bo't a dental pick, which is handy for getting small bits of gunk out of small crevices. A worn-out toothbrush is handy, too.
And as I'm thinking about it, there is an endless variety of items which can be acquired under the general heading of "Gun Cleaning & Maintenance," which you will buy as you need them. Almost none of these will ever be found in a generalized gun cleaning kit.
Finally, you'll need something in which to contain all these items. I find that a medium-sized fishing tackle box suits nicely, and can be picked up cheap @ many rummage sales.
Good luck in designing and making up YOUR OWN cleaning kit!