Incense is very important in Buddhism. It used as an offering on one's altar or as a meditation guide.
It is important to choose one's incense well. It's for that reason
that I stay away from non-natural incense sticks that you can buy at
the dollar store. These are packed with chemicals that can be
dangerous for your health.
Incense in Japan is always refined and its smell is subtle yet
present. It will help to change the mood of a room or put you in
the proper state of mind for your daily meditation.
I personally use Shoyeido incense exclusively. They are made in
Kyoto and have been around for more than 300 years. Their incense
sticks vary from every day incense to special incense that should only
be used for special ceremony. If you ever go to their store in
Kyoto, you can see the ingredients they use to make incense.
I think they are the best incense maker around.
Nippon Kodo is the biggest manufacturer of incense in Japan and their
incense is suitable for every-day use. (Mainichi means every day
in Japanese.) In Japan you can find their products in supermarkets and
convenience stores. People often use their incense to use at the
Buddhist altar or in the bathroom.
Even if they are slightly more mass-market oriented, their products are still quite good.
Japanese incense comes in four forms: powdered, where you burn it
over hot coals, in a cone shape, in a joss stick or in a spiral.
Joss sticks are more common and you can use them to time your meditation. They burn for 20 minutes on average.
I personally use Sei-fu (Fresh breeze) They are quite expensive
but I bought a box of 450 sticks in 2001 and I still have a fifth
left. They have a high content of Kiara (fossilized eucalyptus
wood) which is worth more than gold.
Haku-fun or white cloud is a good alternative and is cheaper.
Coils or spirals are used when you want to have incense for a long time. They will usually last several hours.