Amazon.com has Engine Ice on sale, 4 bottles (1/2 gallon) for $70 and they gave me a $5 promotional discount which may only be good today, or just this morning.
So, 2 bottles = complete coolant change, with 2 more for next spring (2012). For $65 delivered (since I am a Prime member) which is a rocking deal for Engine Ice.
Guess I'll just err on the side of caution and put new coolant in the beast before I do the 10,000 miles I have scheduled for this riding season.
Speaking of which, when I changed the oil and oil filter, I used a gallon bottle of Amsoil 10W40 and for some reason it filled it to the lower line. I expected to have to put a little more in. I might fill it to the top line, but I've always kept my bikes on the lowest acceptable oil level.