i know this is a contentious question. some people say the it's a waste of time and introduces artifacts. others say it protects lenses.

i'm going places that are dusty/sandy but don't plan on throwing the camera around.

dusty sandy, probably 50/50. If you're worried, get one. At least get a UV/Haze filter if you do.. and Multicoated (B+W MHC are great... likewise Hoya Pro1). Don't go cheap.

Use your lens hoods. They do more to protect the lenses than anything else.

I have a UV filter fitted to my 18-55 kit lens and my 55-250 zoom. One is a Canon and one is a Hoya. I have no idea if they make a difference, but I know I don't have one fitted to my 50mm lens and I seem to get less random flare when taking shots in a mixture of low light and flouro bulbs.

Dunno if that's connected in any way at all, or if I am just being a cock.

I use UV filters a lot just becasue I do tend to be in fairly dusty places... Not much in the way of flare issues for me though in part that's becasue of where/ what I shoot.

I use them for protection. If I'm in a rush, the camera can just be thrown into the bag sans lens cap without worrying about damage to an expensive lens. If you can see "artifacts" in your photos caused by a haze filter, you are a much more discriminating photographer than I.