The cost per gallon and shipping make it significantly more expensive that locally purchased antifreeze. Its non-toxic going in, but not non-toxic coming out as there are heavy metals in the cooling system (most likely).
While I feel Amsoil oil and ATF are significantly better than other oils and ATFs I am not sure Amsoil coolant is significantly better than say G-05 or Peak Global.
I just have never seen the value proposition of their antifreeze. The typical coolant systems of today seem to be pretty darn robust with OEM fill. Now if you were planning on keeping your vehicle forever maybe it would be justified.
I had it installed in my GMC Sierra DuraMax Diesel after a triple flush. The Amsoil coolant meets all ASTM specifications for heavy duty diesel engine use. This engine also has a coolant bypass filter installed. Because any cooling system failure would be expensive, I decided to use the Amsoil propylene glycol product. This coolant is rated for extended service life, 7 years or 250,000 miles, however I use the test strips and will send a sample for analysis annually, or to back up a questionable test strip indication. The lower toxicity is also a factor. The cost of these premium fluids (Amsoil lubes and coolant) is not a factor for me, especially when replacing the coolant pump is a $2,000 job, and a replacement engine costs $7,000 plus labor. I plan to keep the truck a minimum of ten years. For the average motorist, with a shorter turn over a cheaper coolant may make just as much sense, providing it is changed every two years.
OF COURSE Amsoil coolant will work in your Mazda 3. Don't you know that Amsoil automotive fluids meet or exceed every spec under the sun? They even magically meet CONFLICTING specs (by exceeding them all!)
With Amsoil coolant, your car will get better gas mileage, handling will improve, freedom will ring, and the world will finally be at peace.