Question about Tamiya Weather Sets

I have been looking at the weathering sets from tamiya and before shelling out up to $8.00 or more per set I wanted to ask anybody that uses them if they believe there worth spending the money or if just regular pastels are better then the tamiya sets dollar for dollar. I like the effects that the set D has for burnt metal on motorcyle exhaust, but think that maybe just regular artist pastels would do the same. Any input would be appreciated…

I have used both their weathing sticks and the sets. They are different from pastels such as Mig pigments. I have not used any other sort of pastels. The two compliment one another. I can not compare them other products pricewise because of that. But I am quite happy with the results I have obtained using them so far.

I also have had good results with the Tamiya weathering sets. I feel they are well worth the money.[tup]

Thank you stikpusher and doc. My next question probably will sound stupid but how long does a set last? or depending on the size of the project how many kits can you do with one? Again probably a stupid question, however kinda curious as I want to try one to finish my kettenkrad project (which is a large scale kit) and weather it fairly realisticly, but wanted to get some feedback here on the forum first.