One piece coated rods are certainly preferable to the kind that come in sections. Bore-Tech and Dewey make excellent rods. I've got both, but I prefer the Bore-Tech because the handle is so much more comfortable and it spins with less effort.

Bore guides are probably not absolutely necessary, but I would not want to clean a rifle bore without one. They work with bolt action rifles and are inserted into the action where the bolt would normally go allowing you to properly clean the rifle from the breech end rather than the muzzle. They align the cleaning rod with the bore which helps to prevent damage to the chamber, throat and rifling that your cleaning rod and implements might cause. Another benefit a bore guide provides is that it seals the chamber which prevents bore solvents from getting into the rifle action, magazine well and trigger assembly. I like the Sinclair bore guides the best, but Stoney Point makes a pretty nice one too. The Sinclair with it's O-ring design seals the chamber better in my opinion.