For about 6 years I worked in a store that sold all of those. Candles sold the most, followed by diffusers, then incense (mostly for mosquito control) and we hardly sold potpourri at all, although if I were to buy anyone of them that is the one I would buy.

Candles are not good for several reasons - fire hazard for one, but petroleum wax candles (most are) are cancer causing and leave a thin layer of soot on your things, windows, and so forth - most people do not notice it but if you burn a lot of candles - then clean your windows there is a film on them - and everything else - even your lungs - nasty. Soy wax and bees wax are better, but still there is a fire hazard.

Diffusers are good, until you spill one, then it is a heck of a mess, the wood floor in the store was ruined by so many customers spilling testers.

Incense can be too over powering.

Potpourri has a dual purpose in that it can be nice to look at and is not as strong to smell.

In general I prefer real air to any of these products and will not buy them.

I do have candles but they are not scented and are for emergencies like if the power goes out.

I like a nice clean house and a good old fashioned candle.

I like and use them all except diffusers.

I love potpouri. I have some in a glass jar in a hutch with pretty things in it like carnival glass, knickknacks, etc. The potpourri has little pine cones in it and flower petals and spices. When you open the hutch, it smells soooo pretty!

I have potpurri on the bathroom counters too. And I put some potpourri in a little saucepan sometimes and simmer it in some water so the whole house smells good! I have some that smells like Christmas time and one like the woods.

Incense is cool! We used it a lot when we were younger...but of course that was the 70s and 80s...we were post hippies! We still use incense now and we have a nice standing golden holder and burner for it. Incense does make the whole house smell pretty too.

Candles...they are so pretty and romantic. I have tons of candles. Only problem is, I have always had cats and so we worry about them jumping up on something and knocking them down or just the danger of candles in general. Of course, we have had to use candles many times during power outages.

We now have two older cats and I have a high fireplace mantle so I do light candles there every so often.

So I do use those three from time to time. They all work great. I think the potpourri works best like I mentioned, in drawers, cabinets, hutches, bathrooms, etc. The incense and the candles are nice for making the whole house smell nice but the candles are definitely the prettiest one to display!

I love the beauty of a burning candle. The scent is wonderful and the light of the candle cannot be matched. They are beautiful at night, especially.

I prefer candles and diffusers. I also like the oil burners you heat with tea candles.

Just last week my daughter mailed me a Yankee Candle® wax warmer and about 15 different wax tarts. I love it. I also think Yankee Candle® candles and diffusers are the best. Other brands are just as expensive but you can barely smell them.

I hate the smell of incense. It doesn't matter what the scent is, they offend me.

I love candles. I have them all over the house. I light them in the evening so when I wake up the house still smells good. I cant light incense because it sets off my sons asthma. I also have diffusers in the the bathrooms and in the closets. I also love Potpourri. It is very pretty to look at and smells good without being too strong. The candles I have usually dont have an super strong smell, and I burn them for about a half hour before I go to bed.

Candles-they emit the aroma better - not all candles aroma last long, but there are 2 brands that I buy but fdont know if I can mention them here. or I swithc to incense, love pachouli