I have one in my 197 at the moment, bought it at Halfords about 6 weeks ago. I like them ,fits perfectly into the cup holder. The scent of mine is called Xtreme Hurricane Breeze . I have another called Xtreme Volcanic Cherry which I have yet to use. I think the Xtreme ones are more intense than the standard ones.
today i bought c. scents - designer polo. first impression-i turned it to the max but it isn't very intensive...i don't know, maybe it will be in a few days.
before that i had the wunderbaum black classic, now that was quite intesive
Normally about £2 Roy, I always get mine from ebay. You should be able to get a 3 for £3.00 deal on ebay somewhere but here is a link I used to get my cherry scent.