The G Series & Super G rods were based on the older Normarks (on Diamaru blanks) and the Carbotecs. I know this is 100% accurate info. Like the Carbotec's the tip section is more like a traditional feeder rod, but as more pressure is exerted into the blank, the rod takes on an almost parabolic action.
The actions of the float rods are the same, with the Light float being virtually identical to a Microlite 2000, Power Float virtually identical to the Titan 2000 & the Specimen Power being almost identical to, yeap you got it, the Avenger 2000.
As I stated before, the original G Series rods are fantastic at the price they sold for originally (and even more so at the discounted price!). The Super G series, I was not overly impressed by as it seemed that Garbolino made changes which were not needed IMHO such as changing the ringing for low profile guides on the feeder rods, which I felt increased line stick to the blank. The only model rods that were improved on with the Super G IMHO were the long rods, 15' & 17'. They are perfectly balanced and feel like you are holding a 13' rod. I have not seen the new rods that were introduced into the 2008 range yet such as the 14' slider, so cannot comment on those.