I took the BRCII in 2006 and the ERC in 2007. This in spite of learning to ride about 1982 and teaching the courses from 1982 to 1984.
I was more than happy to take the BRCII as a veteran rider. If nothing else, it gave me a great practice session. I've been able to learn something new, improve on something old or become aware of myself as a rider in some way in virtually every course of any kind that I've ever taken.
The ERC was great course as well and I used my only bike at the time, the GS550ES. My classmates bikes included a CBR600, a couple of full dress HD's, a Ducati cafe, an Apirlia and several Japanese make cruisers. We all did well and we all passed the class. I'll venture to say that I had the easiest time of it as my bike had the ideal balance between riding position, CoG, handlebar configuration and a relatively small power plant to manage at the 30 mph and under speeds of the course.
As for whether or not to use the Hayabusa or the VTX? Well, I haven't ridden a cruiser as big as the VTX, but I believe each bike will have pro's and con's in the context of the ERC.
Hayabusa: Pro's: Rider CoG (a bit forward, but only slightly), shorter wheelbase (I'm assuming).
Con's: Bar type/full lock range.
VTX: Pro's: Bar type/full lock range.
Con's: Rider CoG (rearward, probably wanna scoot up on the seat as much as possible), longer wheelbase (again, I'm assuming this to be true).
Here's why:
1) Bars: Sport bikes bars tend to be good for small inputs, all that's usually needed at higher speeds. Cruiser bars tend to be easier to use and provide greater range of motion at low speeds such as those in MSF courses.
2) Fork lock-to-lock: Cruisers tend to have much greater steering range from lock to lock making low speed turns and slaloms easier to manage.
3) Turning radius: Sport bikes tend to have shorter wheelbases, requiring less room for low speed turns.
4) Braking: Cruisers are king here due to their longer wheelbases (no stoppies/flips) and heavier weights (more traction).
5) Cornering: Who wouldn't want the sport bike here? ???
6) Slow ride/5 mph riding: The cruisers comfort at low RPM and lower CoG and greater rake/trail is good, but it's offset rider CoG is bad. The sport bikes mated bike/rider CoG's is good, but the higher CoG and preferrer rev range is bad.
The fact of the matter is, that a skilled rider can take virtually any bike through the course and do well. I've seen all sorts of bikes come through and be just fine and I've seen lesser riders not be able to make it through comfortably regardless of the bike.
The choice is yours and you really can't go wrong. Like others have said, pick the bike that you want to improve with the most.
Best of luck!
The AF sportbike instructor course was really a pain. About halfway through I was tempted to go get Captain's bike.
