Here in the UK we have Shell V-Power which is probably the same stuff. I normally use Supermarket fuel (cheap) (ish). The diesel guy who works near me recommends using the better fuel at least once every couple of months. Or do not use the cheaper stuff at all. His reason being that modern injectors have very small nozzle jets of 3 microns and cheap fuel can be a problem with the injector because of impurities in the fuel. As you say it does burn better and gives more MPG. Your Track may have the newer injectors in or the normal 6 micron hole size, it being a car engine. The other industrial engine bikes have injectors that will tolerate rubbish fuel to some extent and using the better fuel may not be desirable.
Building the bike. Top of my list, bottom of the wife's.