Sure ARx has a Niche market, I'm not sure how the numbers would break down, but I would see it like this;
A) People that buy a new car, get it serviced at the Dealer, and Trade before the warranty runs out.
B) People that don't do anything, or 'Maybe' get the oil changed if they think of it, or in desperation if the car is causing problems.
C)People that service the car 'Just the way Dad used to' "Nothing but Penzoline GTX every 3,000 miles and a Flush with Diesel oil" They won't try anything new!
D)People that will buy (and proberbly misuse) any junk they can lay their hands on. They don't know anything about engines, but have good intentions, and like that Warm Fuzzy feeling.
E)People that will only buy over the counter, or from someone they trust.
The list could go on and on.
But What ARx IS, and how it's used (and SOLD) puts it in a Niche
To my mind the best bet would be to sell it as an 'Add on' at Lube outlets; Oil, Treatment AND a Coupon for a follow-up flush.
By the way, What's so special about the 3k and 2.5k follow-up?
I could do 3k in a few days OR in 6 months surly that makes a differance!