So if we say that the GSF1250/1200 has first gen ABS, what gen does the FZ1 have? I ask because the ABS on the bandit is clunky at best, where as the ABS on my cousins Honda SH300 scouter by comparison was very controlled and had a much smoother action.
It's not quite as simple as generations mate, the following is based on my experience of working on them only. As general guide the first systems were really pinched off cars, heavy often dual pumps, with printed circuit board electronics, Bosch was the main leader back then, first I worked on was a BMW late 80's. Then came digital version, all much smaller, faster reacting, better pumps, senors etc etc, these just continue to evolve, which gives you various gens/versions within the type and they're still improving. These are now being overtaken by combined ABS/traction control systems, these have versions as well, early systems having separate electronics controlling each, to the norm and current systems that are joint. Traction control is a whole other ball game and measures, speed, lean, throttle and gear position. I've read they're also experimenting with traction control that can also apply the brakes (like in cars) but this is a very different kettle of fish with 2 wheels, I'm sure in time they'll crack it.
Most manufactures don't make ABS units/system they buy them in, there's not many (at present) Bosch, Honda, Continental, ZF TRW, ATE and I think there's also a Chinese one but I've not worked on Chinese bikes so I don't know. I'm reading that others are now also thinking of coming into the motorcycle ABS market Hitachi for one.
All systems have different design, strengths/weaknesses and then there's of course price. To try and answer your question GSF and FZ1 have the same type non traction control, I don't know if the GSF is the same as FZ1 I've not worked on one. Much is also dependant on where/how it's mounted on the bike, the more 90* bends, connections, ups downs etc the more they become susceptible to micro bubbles. As mentioned some have bleed nipples on the module/pump or they have to be bled in a certain way.
I'm sure if you have a Google you can find, more and no doubt point me in the right direction